While purchasing one item costing ₹ 400, I had to pay the sales tax at 7\% and on another costing ₹ 6400, the sales tax was 9\%. What percent of the sales tax I had to pay, taking the two items together on an average?
(a)8\%
(b)$8 \frac{13}{17} \%$
(c)$8 \frac{15}{17} \%$
(d)$8 \frac{1}{2} \%$
Answer
Answer (as printed): C
Explanation
Total sales tax paid = 7\% of ₹ 400 + 9\% of ₹ 6400 $$=₹\left(\frac{7}{100} \times 400+\frac{9}{100} \times 6400\right)=₹(28+576)=₹ 604 .$$ Total cost of the items $=₹(400+6400)=₹ 6800$. ∴ Required percentage $=\left(\frac{604}{6800} \times 100\right) \%=8 \frac{15}{17} \%$.
Explanation as extracted from the printed page; notation may be imperfect.