Question

A 3 by 3cm grid shows nine 1 by 1 cm squares and uses 24cm of wire.

What length would the wire be for a similar 20 by 20cm sqaure

Answer 1

840 cm

Explanation:

Given that in the question we have, : 9, 1 cm × 1 cm squares setting a 3 × 3 grid.

Therefore wire required in 3 x 3 grid is

3(3+1) + 3(3+1)

= 3 × 4 + 3 × 4

= 24 I'm

Similarly, the length of the wire required in 20 by 20 grid will be

=> 20(20+1) + 20(20+1)

=> 20 × 21 + 20 × 21

=> 420 + 420

= 840cm