Question: Suzy has a lot of skeins of yarn, she has blue, yellow, and red yarn. She has twice as much blue yarn as yellow yarn, and she has twice as much yellow yarn as she has red yarn. If she has X skeins of yarn, how many of the skeins are red, in terms of X?
Options:
(A) X/8
(B) X/7
(C) X/6
(D) X/5
(E) X/4 Random thoughts:
Since the total number of skeins is X, then X = Blue + Yellow + Red
Because there are twice as many Blue as Yellow, then Blue = 2*Yellow
Thus X = 2*Yellow + Yellow + Red, which simplifies to X = 3*Yellow + Red
Because there are twice as many Yellow as Red, then Yellow = 2*Red
Thus X = 3*(2*Red) + Red, which simplifies to X = 7*Red
Therefore Red = X/7 The final answer: (B).