Bert and Harriet collect quarters and pennies. When they wrapped coins to take to the bank, they had $42.50. If they wrapped a total of 410 coins, how many were pennies?

there are 250 pennies

Step-by-step explanation:

q = quarters

p = pennies

q+p = 410 so q = 410 - p

.25q+.01p = 42.50

Replace q with 410 - p

.25 (410-p) +.01p = 42.50

102.50 -.25p +.01p = 42.50

Combine like terms

102.50 -.24p = 42.50

Subtract 105.20 from each side

-.24p = 42.50-102.50

-.24p = -60

Divide each side by -.24

-.24p/-.24 = -60/-.24

p = 250