Question: How much pure alcohol should be added to 700 ml of a 16% solution to make its strength 80%?
A ) 2240 ml B ) 350 ml C ) 224 ml D ) 700 ml
Steps to derive
1 Let x represent the quantity, in ml, of alcohol that needs to be added to make it a 80% solution. Then 700 + x represents the quantity, in ml, of the 80% alcohol solution.
2 And (700 × 16100 ) + x represents the quantity of alcohol in the 80% solution.
3 80% = (700×0.16)+x700+x [Percent of alcohol = quantityofalcoholquantityofsolution.]
480100 = 112+x700+x
5 56000 + 80x = 11200 + 100x [Simplify.]
6 44800 = 20x
7x = 2240 [Solve for x.]
8 2240 ml of pure alcohol must be added to the solution to make it a 80% solution.
