J's answer to KK ng's Primary 5 Maths Area & Volume Singapore question.
done
{{ upvoteCount }} Upvotes
clear
{{ downvoteCount * -1 }} Downvotes
Easy.
Area of 4 triangles = 4 × ½ × base × height
= 2 × 5cm × 12cm
= 120cm²
Length of inner square = 12cm - 5cm = 7cm
Area of inner square = 7cm × 7cm = 49cm²
Total area = 49cm² + 120cm² = 169cm²
Length of big square = √169 cm = 13 cm
OR
169cm² = 13cm × 13cm . Since square has all 4 sides equal in length and area of square = length × length, the length is 13cm.
Perimeter = 13cm × 4 = 52cm
Area of 4 triangles = 4 × ½ × base × height
= 2 × 5cm × 12cm
= 120cm²
Length of inner square = 12cm - 5cm = 7cm
Area of inner square = 7cm × 7cm = 49cm²
Total area = 49cm² + 120cm² = 169cm²
Length of big square = √169 cm = 13 cm
OR
169cm² = 13cm × 13cm . Since square has all 4 sides equal in length and area of square = length × length, the length is 13cm.
Perimeter = 13cm × 4 = 52cm
Date Posted:
3 years ago
360 Tutoring Program