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: Rs. 6000 is lent out in two parts. One part is lent at 5% p.a simple interest and the other is lent at 10% p.a simple interest. The total interest at the end of one year was Rs. 450. Find the ratio of the amounts lent at the lower rate and higher rate of interest?

 Option A: 5:1

 Option B: 5:5

 Option C: 5:8

 Option D: 5:4

 Option E: 5:2

A: Option B
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Q: Question: Plaudia can choose any two of four different candles and any 8 of 9 different flowers for a centerpiece arrangement. Given these choices, how many candle + flower groupings can she select?

 Option A: 54

 Option B: 72

 Option C: 96

 Option D: 144

 Option E: 432

A: Option A
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Q: Question: In a two-digit number, if it is known that its unit's digit exceeds its ten's digit by 4 and that the product of the given number and the sum of its digits is equal to 90, then the number is:

 Option A: 15

 Option B: 27

 Option C: 38

 Option D: 46

 Option E: 48

A:
Option A
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