A 100-ml mixture contains 80% vinegar and 20% sugar. If we want to add more sugar so that we will have 25% of vinegar in the final mixture. How many ml of sugar do we need to add?
You already have 100 mL mixture which is 80% vinegar =80 mL
You wish to reduce the percentage of vinegar from 80% down to 25% of total mixture.
0.25 *[20 mL of sugar + S mL of sugar + 80 mL of vinegar] =80 mL of vinegar.
0.25 * [100 + S] = 80
25 + 0.25S = 80
0.25S = 80 - 25
0.25S = 55
S = 55 / 0.25
S = 220 mL of sugar has to be added to 100 mL mixture of 80% vinegar and 20% sugar.
So, the final mixture will be =20 + 220 mL =240 mL of sugar and 80 mL of vinegar =320 mL mixture.
Finally, 25% of 320 =80 mL of vinegar and 75% (240 / 320) of sugar.
