The task is to generate the correct answer for a given math problem.

Q: Problem: a 9 % stock yields 8 % . the market value of the stock is :

A: rs . 112.50
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Q: Problem: a sum of money at simple interest amounts to rs . 815 in 3 years and to rs . 878 in 4 years . the sum is :

A: 626
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Q: Problem: if the average of 5 x and 8 y is greater than 90 , and x is twice y , what is the least integer value of x ?

A:
4
****