How many ounces of a 35 %35% alcohol solution must be mixed with 1515 ounces of a 40 %40% alcohol solution to make a 38 %38% alcohol solution?

Let be the amount of the 35% solution that will be added. The resulting solution will have a total volume of , 38% of which is alcohol. 40% of 15 is 6, so the 40% solution contributes 6 oz of alcohol. So

oz of the 35% solution need to be added.

168

step-by-step explanation:

first off, we know that he drove 3.5 hours at a rate of 48 mph.

knowing that, we want to see how many miles he drove all-together.

in this case, we can just multiply 48 by 3.5.

48 * 3.5 = 168