# Question

need help to solve this question. thanks..

sorry for my scribble and messy working attempting this question..

For rectangle ABCD,
length ——- 11u

For rectangle ABCD,
length ——- 13u

11u – 2p ——- 28
(11u + 2p ) x 2 = 22u + 4p ——- (13u + 1p) x 2 = 26u + 2p
26u – 22u = 4u ——- 4p – 2p = 2p
2u ——- 1p
11u – (2 x 2u) = 7u ——- 28
1u ——- 28/7 = 4
13u x 1p ——- 13 x 4 x 2 x 4 = 416

Ans : 416 sq cm.

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 Length Breath Perimeter Rectangle ABCD (L – B) 2B (twice of rectangle MNPQ) (L-B) + (L-B) + 2B + 2B = 2L + 2B Rectangle MNPQ L B 2L + 2B (same as rectangle ABCD)

Given: Breath of ABCD is 28cm shorter than its length

(L – B) – 2B = 28

L = 3B + 28

(L – B) = 2B + 28

Given: (L – B) : L = 11 : 13

Length of MNPQ, L = 3B + 28 = 24 + 28 = 52 cm

Area of MNPQ = 52 × 8 = 416 cm2

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thanks for answers.  For using Bigdevil’s method, may i know why is

length of rectangle ABCD= (L-B)? I am unable to find this info from the question?

Perimeter MNPQ = 2L + 2B

Perimeter ABCD = Perimeter MNPQ = 2L + 2B

Breath of ABCD = 2B

Therefore, length of ABCD = 1/2 × ((2L + 2B) – 2B2B) = 1/2 × (2L – 2B) = (L – B)

Hope this clarifies?

thanks very much! i got it! 😀

You are most welcome!  🙂

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Check

Perimeter of MNPQ = 52 + 52 + 8 + 8 = 120 cm

Length of ABCD -> (L – B) = 52 – 8 = 44 cm

Breath of ABCD -> 2B = 16 cm

Perimeter of ABCD -> 44 + 44 + 16 + 16 = 120 cm (same as MNPQ)

ABCD length : MNPQ length

44 : 52

11 : 13

Checked

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