question_answer

How many kilograms of rice costing Rs. 18.30 per kg must be mixed with 126 kg of rice costing Rs. 8.5 5 per kg so that 20% may be gained by selling the mixture at Rs. 14.40 per kg?    

A)                        69 kg

B)  68 kg         

C)  60 kg

D)  61 kg    

Correct Answer: A

Solution :

Selling price of 1 kg of mixture = Rs. 14.40, Gain = 20%

Cost price of 1 kg of mixture = Rs.\[\left( \frac{100}{120}\times 14.40 \right)\]= Rs. 12

(Dearer : Cheaper) = 345 : 630 = 23 : 42

Let x kg of dearer may be mixed with 126 kg of cheaper

Then, \[\frac{x}{126}=\frac{23}{42}\]\[\Rightarrow \]\[x=\left( \frac{23}{42}\times 126 \right)=69\,\,\text{kg}\]

Required quantity = 69 kgC