Question 1036880
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jenny has 40 coins in her purse, comprised completely of dimes and quarters. if the total value of the coins is $8.05, 
how many dimes are in the coin purse?
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Let d = the number of dimes.
Then the number of quarters is (40-d).

The dimes contribute 10d cents to the total.
The quarters contribute 25*(40-d) cents.

The total is 10d + 25(40-d) cents, and it is equal to 805 cents.

It gives you an equation

10d + 25(40-d) = 805.

Simplify and solve:

10d + 1000 - 25d = 805.

-15d = 805 - 1000,

-15d = -195,

d = {{{(-195)/(-15)}}} = 13.

There are 13 dimes and 40-13 = 27 quarters.

<U>Answer</U>.  13 dimes and 27 quarters.

<U>Check</U>.   13*10 + 25*27 = 805.  OK!
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