Jo's collection contains US, Indian and British stamps. If the ratio of US to Indian stamps is 4 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 choice from the following choices
A) 5 : 1  B) 10 : 5  C) 15 : 2  D) 20 : 2  E) 25 : 2
U/I = 4/2   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 = 20 : 10 : 2   i.e. U : B = 20 : 2   Answer: Option 20 : 2
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Jo's collection contains US, Indian and British stamps. If the ratio of US to Indian stamps is 4 to 2 and the ratio of Indian to British stamps is 5 to 1, what is the ratio of US to British stamps?