Hi Jessica,

Following pls find the worked solutions:

Q12.

New L = (120/100) x 50 = 60

New B = (120/100) x 25 = 30

New Area = 60 x 30 = 1800

Original Area = 50 x 25 = 1250

Inc in Area = 1800 - 1250 = 550

% inc in Area = [Inc in Area / Original Area] x 100

= [550 / 1250] x 100 = **44%**

============================

Q13.

40% = (40/100) = (2/5)

25% = (1/4)

Apply <Equal Concept>, we have ..

(2/5) K = (1/4) M

(2/5) K = (2/8) M

Hence, K = 5u ; M = 8u

Given that M - K = 30, we have ...

8u - 5u --> 30

3u --> 30

1u --> 10

Total = 13u --> 13 x 10 = **130**

===============================

Trust the above helps.

Do let me know again should there be any clarification.

Cheers,

Edward