Jo's collection contains US, Indian and British stamps. If the ratio of US to Indian stamps is 7 to 2 and the ratio of Indian to British stamps is 5 to 1, what is the ratio of US to British stamps?	Choose the correct option
A) 5 : 1	B) 10 : 5	C) 15 : 2	D) 20 : 2	E) 35 : 2

Rationale: u / i = 7 / 2 i / b = 5 / 1 since i is multiple of both 2 ( as per first ratio ) and 5 ( as per second ratio ) so let ' s assume that i = 10 i . e . multiplying teh first ratio by 5 and second ration by 2 in each numerator and denominator then , u : i : b = 35 : 21 : 2 i . e . u : b = 35 : 2 answer : option e
Answer: E