Question

The length of each arm of a square was increased by 10%. Let's work out the increase of percentage of area by the rule of Three.​

Answer 1

Answer:

It can be solved by the rule of three as follows

Initial Length of each arm = 100

New length of arm = 110

So increase in area = 110² - 100²

= 12100 - 10000 = 2100

Now, by the rule of three ,

The ratio of increased area to original area is directly proportional to the ratio of increased area to the percentage.

=> 2100 : 10,000 = x : 100

=> 2100 * 100 = 10,000 * x ( by the rule of proportion), where x is increased area.

=> x = (2100 x 100 ) / 10,000

=> x = 21 %

Hope this is helpful for you.