David spends $350 buying his favorite dolls. If he buys only small LemonHead dolls, which are $2 cheaper than the large LemonHead dolls, he could buy 20 more dolls than if he were to buy only large LemonHead dolls. How much does a large LemonHead doll cost?  Choose the correct choice from the following.
A) $ 5	B) $ 7	C) $ 6	D) $ 8	E) $ 9

Rationale: if large doll costs $ 5 , then he can buy 350 / 5 = 70 large dolls and 350 / 3 = 116 small dolls . difference is more than 20 . discard . if large doll costs $ 7 , then he can buy 350 / 7 = 50 large dolls and 350 / 5 = 70 small dolls . difference is 20 , which is we wanted . answer b .
Answer: B