Question 1017916: 1) Stan has 14 bills in his wallet worth $95 altogether. If the wallet contains only $5 and $10 bills, how many bills of each denomination does he have?
2) Libby's drive to work takes 1 hour. If she increases her average speed by 10 miles per hour, the trip takes 3/4 hour. Find the distance she drives to work.
3) Mary and Greta live 21 miles apart. At 1:00 P.M. They start riding their bicycles toward each other and meet at 1:45 P.M. If Greta's average speed is 4 miles per hour faster than Mary's average speed, find Greta's average speed.
4) Margaret gets scores of 88 and 78 on her first two test. What scores must she make on her third test to keep an average of 80 or greater?
5) Sally has 3 times as many nickels as dimes and she has at least 20 coins. At least how many dimes does she have?
Answer by addingup(3677)   (Show Source):
You can put this solution on YOUR website! fivers: f
tenners: t
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f+t = 14 subtract t from both sides:
f = 14-t we'll use this value for f next
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5f+10t= 95 substitute for f
5(14-t)+10t= 95
70-5t+10t = 95
5t = 25
t = 5 and
f = 14-5 = 9
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Check:
5*10 = 50
9*5 = 49
Total:95 We have the correct answer.
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