You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

[Q]: Question: There are 4 boys and 3 girls seated in a row.Find the probability that all girls are together?

 Option A: 1/6

 Option B: 1/7

 Option C: 2/7

 Option D: 3/7

 Option E: 4/7
[A]: Option B


[Q]: Question: Ajay marked the price of his goods 30% more than his C.P. He then sells 1/4th of his stock at a discount of 15%, and half of the stock at the marked price, and the rest at a discount of 30%. Find his gain percentage.

 Option A: 16.5%

 Option B: 15.375%

 Option C: 14.20%

 Option D: 13.37%

 Option E: None of these
[A]: Option B


[Q]: Question: A man on tour travels first 160 km at 64 km/he and the next 160 km at 80 km/hr. The average speed for the first 320 km of the tour is?

 Option A: 71.12

 Option B: 71.19

 Option C: 71.11

 Option D: 71.132

 Option E: 71.16
[A]:
Option C