Solving Grade 3 Math on pages 95 and 96, Volume 1, Cánh Diều Book
Concentrated Practice: Solve exercises on pages 95 and 96 of Math 3 Book Volume 1, Cánh Diều
Concentrated Practice
1. Solve Exercise 1 Page 95 Math Grade 3
Problem: Evaluate the following expressions:
a) 948 - 429 + 479 b) 750 - 101 x 6 c) 998 - (302 + 685)
424 : 2 x 3 100 : 2 : 5 (421 - 19) x 2
Solution Guide:
- If the expression involves only addition and subtraction, perform the operations from left to right.
- If the expression involves addition, subtraction, multiplication, and division, perform multiplication and division first; then perform addition and subtraction.
- When evaluating expressions with parentheses ( ), perform operations inside the parentheses first, and then outside the parentheses.
Answer:
a) 948 - 429 + 479 = 519 + 479
= 998
424 : 2 x 3 = 212 x 3
= 636
b) 750 - 101 x 6 = 750 - 606
= 144
100 : 2 : 5 = 50 : 5
= 10
c) 998 - (302 + 685) = 998 - 987
= 11
(421 - 19) x 2 = 402 x 2
= 804
2. Solve Exercise 2 Page 95 Math Grade 3
Problem: a) Evaluate the following expressions:
(300 + 70) + 500 (178 + 214) + 86
300 + (70 + 500) 178 + (214 + 86)
Solution Guide:
When evaluating expressions with parentheses ( ), perform operations inside the parentheses first, and then outside the parentheses.
Detailed Solution:
a) (300 + 70) + 500 = 870
300 + (70 + 500) = 870
(178 + 214) + 86 = 478
178 + (214 + 86) = 478
b) Observation: The values of the expressions in each column in question a are equal.
c) Example: (625 + 28) + 200 = 853
625 + (28 + 200) = 853
3. Solve Exercise 3 Page 95 Math Grade 3
c) Example: Similar to the expressions in question a.
Phương pháp giải: Khi tính giá trị của các biểu thức có dấu ngoặc () thì trước tiên ta thực hiện các phép tính trong ngoặc.
a) (2 x 6) x 4 = 48
2 x (6 x 4) = 48
(8 x 5) x 2 = 80
8 x (5 x 2) = 80
b) Observation: The values of the expressions in each column in question a are equal.
c) Example: (4 x 9) x 6 = 216
4 x (9 x 6) = 216
4. Solve Exercise 4 Page 95 Math Grade 3
Problem: In the gas tank of a car, there are currently 40 liters of gasoline. Traveling from home to the beach, the car needs to use up 15 liters of gasoline. Returning from the beach to the hometown, the car needs to use up 5 liters of gasoline.
Problem Statement: a) Nhung harvested 60 strawberries, and Xuan harvested 36 strawberries. They evenly distributed all the strawberries into 3 boxes. Choose the correct operation to find the number of strawberries in each box: A. (60 + 36) : 3 = 32 (berries) B. 60 + 36 : 3 = 72 (berries)
b) 800 milk cartons are arranged in rows, with each row containing 4 cartons. Subsequently, these rows of milk cartons are arranged into bins, with each bin containing 5 rows of milk cartons. How many bins of milk are there?
Solution Guide: Read the information in the problem to formulate the appropriate expressions.
Answer:
a) Nhung picked 60 strawberries, and Xuan picked 36 strawberries. They evenly distributed all the strawberries into 3 boxes. The number of strawberries in each box is (60 + 36) : 3 = 32 (berries). Choose A.
b) 800 milk cartons are arranged in rows, with each row containing 4 cartons. Subsequently, these rows of milk cartons are arranged into bins, with each bin containing 5 rows of milk cartons. So, the number of milk bins is 800 : 4 : 5 = 40 (bins). Answer: 40 bins
6. Solve problem 6, Page 96 of Math Textbook for Grade 3
Problem Statement: According to the student, who calculated correctly? Answer: An: 20 - 8 : 4 x 2 = 6 Nam: 20 - 8 : 4 x 2 = 16 Hien: 20 - 8 : 4 x 2 = 19
Solution Guide: If the expression only involves addition, subtraction, multiplication, and division, perform multiplication and division first, then carry out addition and subtraction.
Answer:
20 - 8 : 4 x 2 = 20 - 2 x 2
= 20 - 4
= 16
So, Nam calculated correctly.
Refer to the exercise solutions on pages 95 and 96 of Math Workbook 3, Volume 1, Cánh Diều Book, for a better understanding of theory and concepts. Practice more by working on exercises in the workbook for better mastery.
