Question

A roll of paper 35 cm by 22 cm was cut and 25 cubes with edge 2 cm were made from it. Find the area of paper left.

• A. $120c{m}^2$
• B. $170c{m}^2$
• C. $180c{m}^2$
• D. $200c{m}^2$

Answer 1

The correct option is B $170c{m}^2$

Area of roll of paper$=35\times 22c{m}^2$

$=770c{m}^2$

Surface area of 1 cube with side $a$ = $6a^2$

Surface area of 25 cubes with side 2 cm $=25\times 6\times 4$

$=600c{m}^2$

Area of paper left $=770-600=170c{m}^2$