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: The cost of Type 1 material is Rs. 15 per kg and Type 2 material is Rs.20 per kg. If both Type 1 and Type 2 are mixed in the ratio of 2 : 3, then what is the price per kg of the mixed variety of material?

 Option A: Rs. 19

 Option B: Rs. 16

 Option C: Rs. 18

 Option D: Rs. 17

 Option E: Rs. 21

A: Option C
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Q: Question: The compound ratio of 1:3, 3:2 and 4:5?

 Option A: 1:9

 Option B: 1:7

 Option C: 1:2

 Option D: 2:5

 Option E: 1:4

A: Option D
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Q: Question: Find the fourth proportional to 2.5, 4.6 and 7.6?

 Option A: 13.98

 Option B: 14.98

 Option C: 15.18

 Option D: 15.34

 Option E: 16

A:
Option A
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