Because he’s taxed by his home planet, Mork pays a tax rate of 45% on his income, while Mindy pays a rate of only 15% on hers. If Mindy earned 4 times as much as Mork did, what was their combined tax rate?  Answers.
A) 19 %	B) 21 %	C) 23 %	D) 25 %	E) 27 %

Rationale: "let x be mork ' s income , then mindy ' s income is 4 x . the total tax paid is 0.45 x + 0.6 x = 1.05 x 1.05 x / 5 x = 0.21 the answer is b ."
Answer: B