Question

the ratio of the length of school ground to its width is 5:2. find its length and if its breadth is 40 m

Answer 1

let length be X .
according to the question:
5:2::X :40
product of extremes = product of means .
=> 5 × 40 = 2 × X
=> 200=2x
=> 2x = 200
=> X=200/2
=> X = 100
hence the required length is 100 m