SOLUTION: Please help, I can't seem to get these problems set up right.1.) A medicated first aid spray on the market is 78% alcohol by volume. If the manufacturer has 50 liters of the spray

Algebra ->  Proportions  -> Lessons -> SOLUTION: Please help, I can't seem to get these problems set up right.1.) A medicated first aid spray on the market is 78% alcohol by volume. If the manufacturer has 50 liters of the spray       Log On


   



Question 100798This question is from textbook mathematical ideas
: Please help, I can't seem to get these problems set up right.1.) A medicated first aid spray on the market is 78% alcohol by volume. If the manufacturer has 50 liters of the spray containing 70% alcohol , how much pure alcohol should be added so that the final mixture is the required 78% alcohol? (hint pure alochol is 100%) 2.) There is a box containing 44 coins, consisting of pennies, dimes, and quarters. The number of pennies is equal to the number of dimes, and the total value is $4.37. How many of each denomination of coins are in the box?
Thanks in anvance for your help!!
This question is from textbook mathematical ideas

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
1.) 50(70%)+x(100%)=(50+x)(75%) ... 35+x=37.5+.75x ... .25x=7.5 ... x=30

2.) let x=pennies or dimes ... 1x+10x+25(44-2x)=437 ... 1100-39x=437 ... 663=39x ... x=17 ... 44-2x=10