Hướng dẫn giải bài tập tính giá trị biểu thức lớp 4 chi tiết nhất

Calculating the value of grade 4 expression is one of the important topics, often appearing in math exams, as well as practical applications. So, to help them conquer this all kind, the following content Mầm non Cát Linh will analyze in detail.

Rules for calculating the expression value in Grade 4 Mathematics

The main expression is the numbers connected through calculations such as addition, subtraction, multiplication, and division. And the value of the expression is the result that we calculate after accurate implementation of the calculations in that expression.

In mathematics, the rules for calculating the expression value will include:

Rule 1: In an expression, if there is only addition and subtraction or multiplication and division, we perform calculations according to the rule from left to right.

Example: 1234 + 4567

Perform calculations in order from right to left we have:

1 plus 4 equals 5, writing 5

2 plus 5 equals 7, writing 7

3 plus 6 equals 9, writing 9

4 plus 7 equals 11, writing 11

Results of expression value 1234 + 4567 = 57911

Rule 2: In an expression, if it contains a circular bracket (), we will have to perform the calculation in the brackets first, then perform the external calculation. In case the expression has many types of parentheses, the round parentheses () prioritize the priority, then to square brackets [] And finally, the braces {}.

For example:

Calculate the expression value: 60320 – (32578 + 17020)

= 60320 – 49598 = 10722

Rule 3: In the expression, consisting of addition, subtraction, multiplication, and division we will prioritize the following rule “multiply, divide before – plus, subtract later”.

Example: Calculate the expression value: 134415 – 134415: 45 = 134415 – 2987 = 131428

Suggest a quick calculation method for additional expressions:

• So the group of terms in the grouped expression has the sum of tens/hundred/thousand numbers to be easier to calculate.
• Apply the combination properties of the spell plus the general formula: A + B + C = A + C + B = C + A + B to calculate accurately.

The common types of exercises calculating the value of the common grade 4 expression

In the 4th grade math program, they will often encounter some exercises on calculating the expression value as follows:

Form 1: Group of terms in groups of groups with total/difference is the rounds of tens/hundred/thousand … then add/subtract the results.

Example: Fast calculation of expression 349 + 602 + 651 + 398

Solution:

349 + 602 + 651 + 398

= (346 + 651) + (602 + 398)

= 1000 + 1000

= 2000

Form 2: Apply the properties of some multiplier with a sum, some core with one difference, a sum divided by a number….

Example: Calculate the expression value 19 × 82 + 18 × 19

Solution:

19 × 82 + 18 × 19

= 19 × (82 + 18)

= 19 × 100

= 1900

Form 3: Apply some knowledge about the sequence to be able to calculate the value of the most convenient way.

Formula: Number of terms = (last term – the first term): distance + 1

After we find the term of the expression with the equidist number sequence, we can quickly perform the sum of those sequences according to the following steps:

• Step 1: Find the corresponding number of the given sequence.
• Step 2: Perform the number of pairs that can be made from those terms (take the number of terms divided by 2).
• Step 3: Group of terms into groups, usually the first term group with the end of the sequence, every one to the end.
• Step 4: Calculate the value of each pair of numbers (the values ​​of each pair are equal)
• Step 5: Perform the sum of the sequence by taking the number of pairs with the corresponding value of a pair.

For example, calculate the sum of natural numbers from 1 to 100.

Solution:

Natural numbers from 1 to 100 with the numbers are:

(100 – 1): 1 + 1 = 100 (Number)

100 numbers forming pairs are:

100: 2 = 50 (pairs)

We have: 1 + 2 + 3 + 4 + 5 + ……….. + 96 + 97 + 98 + 99 + 100

= (1 + 100) + (2 + 99) + (3 + 98)

+ (4 + 97) + (5 + 96) + …..

= 101 + 101 + 101 + 101

+101 +… 101

= 101 × 50 = 5050

Exercise calculating the value of the 4th grade math expression

Below Mầm non Cát Linh will summarize some exercises on calculating the value of the 4th grade expression for the reference:

Exercise with solutions

Exercise 1: Calculate the value of the following expression:

a) 16 + 4748 + 142 -183

b) 472819 + 174 – 19 x 98

c) 5647 – 18 + 1874: 2

d) 87 x 192 – 216: 6

– Solution instructions:

Follow the rules of multiplication, division and addition. We have:

a) 16 + 4748 + 142 – 183 = (4748 + 142) – 183 + 16 = 4890 – 167 = 4723

b) 472819 + 174 – 19 x 98 = 472819 + 174 – 1862 = 471131

c) 5647 – 18 + 1874: 2 = 5629 + 937 = 6566

d) 87 x 192 – 216: 6 = 16704 – 36 = 16668

Exercise 2: Find y know:

a) Yx 5 = 1948 + 247

b) Y: 3 = 190 – 90

c) Y – 8357 = 3829 x 2

d) Yx 8 = 182 x 4

– Solution instructions:

a) Yx 5 = 1948 + 247

Yx 5 = 2195

y = 2195: 5

y = 439

b) Y: 3 = 190 – 90

Y: 3 = 100

y = 100 x 3

y = 300

c) Y – 8357 = 3829 x 2

Y – 8357 = 7658

y = 7658 + 8357

y = 16015

d) Yx 8 = 182 x 4

yx 8 = 728

y = 728: 8

y = 91

Exercise 3: Calculate the expression value in the most convenient way.

a) 103 + 91 + 47 + 9

b) 261 + 192 – 11 + 8

c) 915 + 832 – 45 + 48

d) 1845 – 492 – 45 – 92

Solution instructions:

Follow the rules of the expression containing addition, except we have:

a) 103 + 91 + 47 + 9 = (103 + 47) + (91 + 9) = 150 + 100 = 250 = 250

b) 261 + 192 – 11 + 8 = (261 – 11) + (192 + 8) = 250 + 200 = 450

c) 915 + 832 – 45 + 48 = (915 – 45) + (832 + 48) = 870 + 880 = 1750

d) 1845 – 492 – 45 – 8 = (1845 – 45) – (492 +8) = 1800 – 500 = 1300

Exercise 4: Calculate the value of the following calculation:

a) 1245 + 2837

b) 2021 + 194857

c) 198475 – 28734

d) 987643 – 2732

Place and calculate, the digits are in line together. Perform calculation from right to left. We have:

a)

7 plus 5 equals 12, writing 2 remember 1

3 plus 4 equals 7 add 1 more equal to 8, write 8

8 add 2 equals 10, write 0 remember 1

2 plus 1 equal to 3 add 1 equal to 4, write 4

So 1245 + 2837 = 4082

b)

7 plus 9 equals 16, writing 6 remember 1

5 plus 1 equal to 6 add 1 to 7, write 7

8 plus 0 equal to 8, write 8

4 plus 2 equals 6, writing 6

Lower 19 to the result of 196876

So 2021 + 194857 = 196876

c)

5 minus 4 equals 1, writing 1

7 minus 3 equals 4, writing 4

4 Can not deducted 7 borrowed 1, 14 minus 7 equals 7, writing 7 remember 1

Borrow 1 to 18 deducted 9 equal to 9, write 9 remember 1

2 Add 1 equal to 3, 9 minus 3 equals 6, Write 6

1 minus 0 equal to 1, write 1

So 198475 – 28734 = 169741

d)

3 Subtract 2 equals 1, write 1

4 minus 3 equals 1, writing 1

6 Not deducted for 7, borrowed 1 to 16 deducted 7 equal to 9, write 9 remember 1

2 Add 1 equal to 3, 7 minus 3 equals 4, Write 4

Lower 98 to get results: 987643 – 2732 = 984911

Exercise 5: Two days the store sells 5124 liters of oil, knowing that the second day sells less than the first day of 124 liters. Ask how many liters of oil every day.

Solution instructions:

Each day sells the number of liters of oil is:

(5124 – 124): 2 = 5000: 2 = 2500 (liters of oil)

The first day sold more than the 2nd day is:

2500 + 124 = 2624 (liters of oil)

So the first day sold 2624 liters, the second day sold 2500 liters of oil.

Applied exercises

Lesson 1: Fast calculation:

A, 237 + 357 + 763

b, 2345 + 4257 – 345

c, 4276 + 2357 + 5724 + 7643

D, 3145 + 2496 + 5347 + 7504 + 4653

E, 2376 + 3425 – 376 – 425

g, 3145 – 246 + 2347 – 145 + 4246 – 347

Lesson 2: Fast calculation:

A, 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5 + 5

b, 25 + 25 +25 +25 + 25 + 25 + 25 + 25

c, 45 + 45 +45 + 45 +15 + 15 +15 + 15

D, 2 + 4 + 6 + 8 +10 + 12 +14 + 16 +18

E, 125 +125 +125 +125 – 25 – 25 – 25 – 25 -25

Lesson 3: Fast calculation:

A, 425 × 3475 + 425 × 6525

b, 234 × 1257 – 234 × 257

c, 3876 × 375 + 375 × 6124

D, 1327 × 524 – 524 × 327

E, 257 × 432 + 257 × 354 + 257 × 214

f, 325 × 1574 – 325 × 325 – 325 × 249

G, 312 × 425 + 312 × 574 + 312

H, 174 × 1274 – 175 × 273 – 175

Lesson 4: Fast calculation:

A, 4 × 125 × 25 × 8

b, 2 × 8 × 50 × 25 × 125

c, 2 × 3 × 4 × 5 × 50 × 25

D, 25 × 20 × 125 × 8 – 8 × 20 × 5 × 125

Lesson 5: Fast calculation:

A, 8 × 427 × 3 + 6 × 573 × 4

b, 6 × 1235 × 20 – 5 × 235 × 24

c, (145 × 99 + 145) – 143 × 101 – 143

d, 54 × 47 – 47 × 53 – 20 – 27 – 27

Lesson 6: Fast calculation:

A, 10000 – 47 × 74 – 47 × 26

b, 3457 – 27 × 48 – 48 × 73 + 6543

Lesson 7: Let A = 2009 × 425 and B = 575 × 2009. Excluding A and B, please calculate the results of A + B?

Lesson 8: Calculate fast

(145 × 99 + 145) – (143 × 102 – 143 × 2) + 54 × 47 – 47 × 53 – 20 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27 – 27

Lesson 9: Given the expression A = 1496: (213 – x) + 237

a) Calculate a when x = 145

b) Find x to a = 373

Lesson 10: Calculate

A, 54 × 113 + 45 × 113 + 113

b, 54 × 47 – 47 × 53 – 20 – 27 – 27

c, 10000 – 47 × 72 – 47 × 28

D, (145 × 99 + 145) – (143 × 101 – 143)

E, 1002 × 9 – 18

F, 8 × 427 × 3 + 6 × 573 × 4

G, 2008 × 867 + 2009 × 133

Lesson 11: Calculate the value of the expression

A, 234576 + 578957 + 47958B, 41235 + 24756 – 37968C, 324586 – 178395 + 24605D, 254782 – 34569 – 45796666

Lesson 12: Calculate the value of the expression

A, 967364 + (20625 + 72438) B, 420785 + (420625 – 72438) C, (47028 + 36720) + 43256D, (35290 + 47658) – 57302E, (72058 – 45359) + 26705F, (60320 – 32578) – 17020202020202020201202019)

Lesson 13: Calculate the value of the expression

A, 25178 + 2357 x 36b, 42567 + 12336: 24C, 100532 – 374 x 38D, 2345 x 27 + 45679E, 12348: 36 + 2435F, 134415 – 134415: 45g, 235 x 148 – 148H, 115938: 57 – 57 – 57 – 57

Lesson 14: Calculate the value of the expression

A, 324 x 49: 98B, 4674: 82 x 19C, 156 + 6794: 79D, 7055: 83 + 124E, 784 x 23: 46F, 1005 – 38892: 42: 42

Lesson 15: Calculate the value of the expression

A, 427 x 234 – 325 x 168b, 16616: 67 x 8815: 43C, 67032: 72 + 258 x 37d, 324 x 127: 36 + 873

Lesson 16: Calculate the value of the expression

A, 213933 – 213933: 87 x 68b, 15275: 47 x 204 – 204C, 13623 – 13623: 57 – 57D, 93784: 76 – 76 x 14

Lesson 17: Calculate the value of the expression

a, 48048 – 48048 : 24 – 24 x 57b, 10000 – (93120 : 24 – 24 x 57)c, 100798 – 9894 : 34 x 23 – 23d, 425 x 103 – (1274 : 14 – 14)e, (31850 – 730 x 25) : 68 – 68f, 936 x 750 – 750 : 15 -15

Lesson 18: Calculate the value of the expression

A, 17464 – 17464: 74 – 74 x 158b, 32047 – 17835: 87 x 98 – 98C, (34044 – 324 x 67): 48 – 48D, 167960 – (167960: 68 – 68 x 34)

Lesson 19: Given the expression P = M + 527 x n. Calculate P when m = 473, n = 138.

Lesson 20: Give the expression P = 4752: (x – 28)

a, Calculate p when x = 52

b, Find x to p = 48

Lesson 21: Give the expression A = 1496: (213 – x) + 237

a, Calculate A when x = 145

b, Find x to a = 373

Lesson 22: Give the expression b = 97 x (x + 396) + 206

a, Calculate B when x = 57

b, Find x to b = 40849

Lesson 23: Write each expression after the achievement of factors:

A, 12 + 18 + 24 + 30 + 36 + 42

b, mm + pp + xx + yy

c, 1212 + 2121 + 4242 + 2424

Lesson 24: Given the expression A = 3 x 15 + 18: 6 + 3. Put the parentheses on the appropriate position so that the expression A has a value of (presenting the steps)

a, 47

b, the smallest number possible

c, the largest number possible

The secret to learning math grade 4 calculates the value of expression effectively

For the knowledge of calculating the value of the 4th grade math expression, to help them understand, easy to conquer this exercise, do not ignore the following tips:

• Understand the rules for calculating the expression value: Only when grasping these rules will the response to the accurate calculation, not confused between the signs.
• Applying the properties of addition/subtraction/multiplication/division: For each calculation, there will be accompanying properties, so the application of those properties will also support the calculation of the expression value more accurate.

See also:

Addition

Subtraction properties

Multiplication properties

Division

• Practicing regular practice: Practicing regular practice is the best way for them to improve their knowledge. So, in addition to doing homework in textbooks, they can practice more exercises on the internet, practice exam questions, apply them to practice, …
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Conclude

Above is the knowledge about the value of the 4th grade expression.

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