One quantity of wheat at Rs 9.30 per Kg is mixed with another quality at a certain rate in the ratio 8:7. If the mixture so formed be worth Rs 10 per Kg, what is the rate per Kg of the second quality of wheat?
Choose the correct choice from the following options:  A) Rs 12.47  B) Rs 10.80  C) Rs 10.80  D) Rs 47.66  E) None of these
Explanation :   Let the rate of second quality be Rs x per Kg.   C.P of 1Kg wheat of 1st kind = Rs 9.30   C.P of 1 Kg wheat of 2nd kind = Rs. x.   Mean price = Rs 10.   The given ratio is 8 : 7.   Rs 9.30 Rs x   \ /   (Mean Price)   Rs 10   / \   x-10 : 0.7   8 : 7   Then, the ratio is :-   =&gt;(x-10) : 0.7 = 8 : 7.   =&gt;7x -70=5.6.   =&gt;x=75.6/7.   Hence, the required amount is 10.80 per Kg.   Answer : Rs 10.80
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One quantity of wheat at Rs 9.30 per Kg is mixed with another quality at a certain rate in the ratio 8:7. If the mixture so formed be worth Rs 10 per Kg, what is the rate per Kg of the second quality of wheat?