Question: jo ' s collection contains us , indian and british stamps . if the ratio of us to indian stamps is 5 to 2 and the ratio of indian to british stamps is 4 to 1 , what is the ratio of us to british stamps ?
A) 5 : 1
B) 10 : 5
C) 15 : 2
D) 20 : 2
E) 25 : 2
Correct answer: D
Grade: 7 | Topic: Ratios and proportions | Difficulty: Medium | Standard: 7.RP.A.2