Buzz
Students are encouraged to refer to the solution manual for Grade 4 math problems on pages 67 and 68 of VBT workbook, Volume 2, Concentrated Practice, Exercise 141 to visualize the solving method or compare their answers for exercises 1, 2, 3, and 4 to see if they are correct. This can help them tackle related exercises on finding two numbers when given their sum and ratio.
Solving Grade 4 math problems on pages 67 and 68 of VBT workbook, Volume 2, Concentrated Practice, Exercise 141
1. Solve Exercise 1 - Grade 4 math workbook Volume 2, page 67
Problem:
Fill in the blanks with ratios:
Solution Method
Apply the definition: The ratio of a to b is a : b or a/b (where b is not equal to 0).
Answer:
2. Solve Exercise 2 - Grade 4 math workbook Volume 2, page 67
Problem:
Two bags of rice weigh 54 kg in total. The first bag weighs 4/5 as much as the second bag. How many kilograms does each bag weigh?
1. Solve the problem visually: Consider the amount of rice in the first bag (acting as the smaller quantity) divided into 4 equal parts, then the amount of rice in the second bag (acting as the larger quantity) divided into 5 equal parts.
2. Find the total number of equal parts.
3. Determine the value of 1 part by dividing the sum of the two quantities by the total number of equal parts.
4. Find the smaller quantity (multiply the value of one part by the number of parts of the smaller quantity).
4. Find the smaller number (multiply the value of one part by the number of parts of the smaller number).
5. Find the larger number (multiply the value of one part by the number of parts of the larger number or subtract the smaller number from the sum of the two numbers).
Note: Steps 3 and 4 can be combined into one step.
Answer
According to the diagram, the total number of equal parts:
4 + 5 = 9 (parts)
The amount of rice in the first bag is:
54 : 9 x 4 = 24 (kg)
The weight of rice in the second bag is:
54 : 9 x 5 = 30 (kg)
Answer: First bag: 24 kg; Second bag: 30 kg
3. Solve Exercise 3 - Grade 4 math workbook Volume 2, page 67
Problem
Fill in the blanks with appropriate numbers
Solution Method
Find two numbers according to the problem of finding two numbers when given their sum and ratio.
Solution Method
- Calculate the area of the shapes using the following formulas:
+) Area of a square = side x side.
+) Area of a rectangle = length x width.
- Find the ratio of the areas of two shapes based on the definition:
The ratio of a to b is a : b or a/b (where b is not equal to 0).
Answer
The area of the square is:
The area of a square is 9 square meters (m2).
The area of a rectangle is:
The area of a square is 15 square meters (m2).
The ratio of the area of a square to a rectangle is 9/15 or 3/5.
Solution: 9/15 or 3/5
You are viewing the instructions for solving math problems for 4th grade, page 67, 68 of VBT exercise book 2 Consolidated practice exercise 141, you can review the instructions on Solving math problems for 4th grade page 65, 66 VBT exercise book 2 Consolidated practice or preview the instructions on Solving math problems for 4th grade page 69 VBT exercise book 2 Finding two numbers given their difference and their ratio to understand more about the lesson.
