Question

A mirror 15 cm long and 12 cm wide is to be framed with a 3 cm wide frame. find the area of the frame.if the cost of the frame is rs 25 per cm2, find the cost of the frame.

Answer 1

First find the area of the mirror and frame together and the area of just the mirror. (Area= 2l+2h)

Area without frame (A1) = 2(15) + 2(12)

A1 = 30+24               A1= 54 cm²

Area with frame (A2) = 2(15 + 3) + 2(12+3)

A2 = 2(18) + 2(15)            A2 = 36+30            A2 = 66 cm²

Subtract the area of the just the mirror (A1) with the area of the mirror and frame (A2).

A2 - A1 = Area of frame

66 - 54 = 12 cm²

To find the price for the frame you would multiply the amount per centimeter squared by the area of the frame. Say the amount is 75 cents per centimeter squared. It would look like $0.75 x 12 cm² = C. Your answer for C would then be $9. I hope this helps!