Question

How many kilos of tea worth Rs. 72 per kg should be mixed with 10 kg of tea worth Rs. 90 per kg to produce a mixture which will cost Rs. 78 per kg?

Answer 1

Let ‘x’ kg of tea worth Rs 72 per kg be mixed .
Total cost = 72x + 90.10
= 72x + 900
Total ‘kg’ = x + 10
$\therefore costperkg=\frac{72x+900}{x+100}$
$\Rightarrow 78=\frac{72x+900}{x+10}$
$\Rightarrow 78x+780=72x+900$
$\Rightarrow 6x=120$
$\therefore x=20$