Ask Singapore Homework?
Upload a photo of a Singapore homework and someone will email you the solution for free.
See 1 Answer
done
{{ upvoteCount }} Upvotes
clear
{{ downvoteCount * -1 }} Downvotes
This is how you can cut the figure . Refer to the comment for workings
Date Posted:
4 years ago
You can combine unshaded area 1 and unshaded area 2 to get 1 small unshaded square.
The figure can be cut into 4 squares.
The 4 small squares are identicall
and have ¼ the area of the big square.
Area of big square = 16cm x 16cm
= 256cm²
Area of 1 small square = 256cm² ÷ 4
= 64cm²
Diameter of the semicircle is half of the big square's length
= 16cm ÷ 2 = 8cm
Its radius = 8cm ÷ 2 = 4cm
Area of semicircle
= ½ x π x 4cm x 4cm
= 8π cm²
Total area of Q
= Area of the unshaded square + area of semicircle
= 64cm² + 8πcm²
= (64 + 8π)cm²
The figure can be cut into 4 squares.
The 4 small squares are identicall
and have ¼ the area of the big square.
Area of big square = 16cm x 16cm
= 256cm²
Area of 1 small square = 256cm² ÷ 4
= 64cm²
Diameter of the semicircle is half of the big square's length
= 16cm ÷ 2 = 8cm
Its radius = 8cm ÷ 2 = 4cm
Area of semicircle
= ½ x π x 4cm x 4cm
= 8π cm²
Total area of Q
= Area of the unshaded square + area of semicircle
= 64cm² + 8πcm²
= (64 + 8π)cm²
i dont understand
Refer to the figure and see how it's cut up. Which part is unclear?
Perimeter of P is made up of 3 curved sections of a quadrant, 1 radius of the quadrant and the curved section of the semicircle.
3 sections of a quadrant circle is the same as ¾ of a full circle's circumference.
Perimeter of these 3 sectioms
= ¾ x πd = ¾ x π x 16cm
= 12πcm
The length of the semicircle's curved section = ½ x πd
= ½ x π x 8cm
(remember its diameter is 8cm since it's half of the square length)
= 4πcm
1 radius of the quadrant
= 16cm ÷ 2 = 8cm
Total perimeter of P
= 12πcm + 4πcm + 8cm
= 16πcm + 8cm
= (16 + 8π)cm
3 sections of a quadrant circle is the same as ¾ of a full circle's circumference.
Perimeter of these 3 sectioms
= ¾ x πd = ¾ x π x 16cm
= 12πcm
The length of the semicircle's curved section = ½ x πd
= ½ x π x 8cm
(remember its diameter is 8cm since it's half of the square length)
= 4πcm
1 radius of the quadrant
= 16cm ÷ 2 = 8cm
Total perimeter of P
= 12πcm + 4πcm + 8cm
= 16πcm + 8cm
= (16 + 8π)cm
ok now i understand. THANK YOU SO MUCH
Great. Amended the answer for b), it should be (16π + 8)cm instead of (20 π + 8)cm