Find Tuition/Enrichment Centres

AskQ logo

STUCK ON HOMEWORK?

ASK FOR HELP FROM OUR KIASUPARENTS.COM COMMUNITY!

Question

Answer

Area of rectangle = 21 × 28 = 588 

 

Since B is the midpoint of the diagonal QS, the perpendicular distance of B from PS must be half of PQ. So area of triangle PAS = 0.5 × 21 × 3/5 × 14 = 88.2

Area of triangle PQB = 0.5 × 28 × 10.5  = 147

Area of triangle SRC = 126

Shaded area = 588 – 88.2 – 147 – 126 = 226.8

Fraction that is shaded = 226.8/588 = 27/70

1 Reply 0 Likes ✔Accepted Answer

PAS = 0.5 × 21 × 3/5 × 14 = 88.2

 

how u get 3/5?

 

1 Reply 0 Likes

Ratio is 3:2.

Point B is the midpoint..

Half 0f 28 is 14.

Perpendicular height is 3/5 of 14 cm. 

Or 3/10 of 28 cm. 

1 Reply 0 Likes

understood thanks

 

 

1 Reply 0 Likes

As a courtesy, please accept the answer if you agree with it. 

Thank you. 

0 Replies 0 Likes

Another way of doing this is by calculating the fraction.

Area of rectangle = L × B

Area of triangle SRC = 1/2 × L × 3/7 B = 3/14 L×B

Area of triangle PQB = 1/2 × L × 1/2 B = 1/4 L × B

Area of triangle PSA = 1/2 × B × 3/10 L = 3/20 L × B

Area of unshaded part = (3/14 + 1/4 + 3/20) L × B  = 43/70 L × B

Area of shaded part = (1 – 43/70) L × B = 27/70 L × B

Fraction that is shaded is 27/70.

0 Replies 0 Likes
Find Tuition/Enrichment Centres