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We have a jar of coins, all pennies and quarters. All together, we have 302 coins, and the total value of all coins in the jar is $ 42.86. How many pennies are there in the jar?

User Danikaze
by
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1 Answer

2 votes

Answer:

There are 136 pennies in the jar

Explanation:

The expression for the total value of money Aria has is;

Penny has a value of= $0.01

Quarter has a value of= $0.25

Total value=(value of a quarter×number of quarters)+(value of a penny×number of pennies)

where;

Total value=$42.86

Value of a quarter=$0.25

number of quarters=x

Value of a penny=0.01

number of pennies=y

replacing;

42.86=(0.25×x)+(0.01×y)

0.25 x+0.01 y=42.86....equation 1

The total number of coins=number of quarters+number of pennies

where;

Number of quarters=x

Number of pennies=y

Total number of coins=302

replacing;

x+y=302....equation 2

Combine equation 1 and 2 and solve simultaneously;

1(x+y=302)1

-

4(0.25 x+0.01 y=42.86)

x-4(0.25 x)+y-(0.01 y×4)=302-(4×42.86)

0+0.96 y=130.56

0.96 y=130.56

y=130.56/0.96

y=136

Replace the value of y in equation 2

x+136=302

x=302-136

x=166

Number of quarters=x=166

Number of pennies=y=136

User Stephen Byrne
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