a local grocer mixed 3 qualities of coffee a, b, c proceed at a price 79/- 64/- 62/- per kg respectively at the ratio 1:2:4. to 4 kg of the mixture he adds quantities of a and c which are in the ratio 1:5. and sells at 77.88/- per kg with a profit…

a local grocer mixed 3 qualities of coffee a, b, c proceed at a price 79/- 64/- 62/- per kg respectively at the ratio 1:2:4. to 4 kg of the mixture he adds quantities of a and c which are in the ratio 1:5. and sells at 77.88/- per kg with a profit of 20%

what is the quantity of a mixed to the mixture €‹.