Bunuel
In a recent basketball game, Shenille attempted only three-point shots and two-point shots. She was successful on 20% of her three-point shots and 30% of her two-point shots. Shenille attempted 30 shots. How many points did she score?
(A) 12
(B) 18
(C) 24
(D) 30
(E) 36
Solution:Since 20% = 1/5 and 30% = 3/10, we see that the number of three-point shots must be a multiple of 5 and the number of two-point shots must be a multiple of 10. Since the total number of shots attempted is 30, there must be either 20 three-point shots and 10 two-point shots OR 10 three-point shots and 20 two-point shots.
In the former case, the total number of points she scored is 1/5 x 20 x 3 + 3/10 x 10 x 2 = 12 + 6 = 18. In the latter case, the total number of points she scored is 1/5 x 10 x 3 + 3/10 x 20 x 2 = 6 + 12 = 18. We see that in either case, she scored 18 points.
Answer: B