Solving Exercise 3 on Pages 100 and 101 in the 5th-grade Math Textbook

Step-by-step Solution for Exercise 3 on Pages 100 and 101 in the 5th-grade Math Textbook

Solution Method:
Upon observing the diagram, we find that the area of the given shape is the sum of the rectangle's area and the combined area of two semicircles.
- Determine the length of the rectangle.
- Calculate the area of the rectangle by multiplying the length (found earlier) by the width (known).
- Compute the area of two semicircles when the radius is given using the formula: Area = radius x radius x 3.14.
- Find the area of the given shape by adding the area of the rectangle to the combined area of the two semicircles. 

Answer:
The length of the rectangle is:
           7 x 2 = 14 (cm)
The area of the rectangle is:
          14 x 10 = 140 (cm²)
The area of the two semicircles is:
          7 x 7 x 3.14 = 153.86 (cm²)
The given shape's area is:
         140 + 153.86 = 293.86 (cm²)
                        Answer: 293.86cm².

Mytour has just guided through solving exercise 3 on pages 100 and 101 in the 5th-grade Math textbook. Additionally, we've suggested solutions for Exercise 1 on Pages 100, 101 SGK Toán 5, Exercise 2 on Pages 100, 101 SGK Toán 5, and Exercise 4 on Pages 100, 101 SGK Toán 5. Check out our instructions on Solving 5th-grade Math exercises on pages 100 and 101 to master the subject!