[单选题]
Suppose a family has an inco w7(4qkuvrj3amk.d5 fg*9okrzu(lh 5 x0uk w+me of ,al :agkg0 s rsbbt6z2r*by *-US $\$$50000 and it pays a tax of US $\$$15000. Calculate the average tax rate.
A. 30 %
B. 33.3 %
C. 42.8 %
D. 70 %
参考答案: A
本题详细解析: Average tax rate = $\frac{50 000}{15 000}\times100$=30%
