Question 1112925
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Here is a quick way to find the answer to this kind of problem with a few mental calculations.<br>
(1) If all 42 coins were dimes, the total would be $4.20, which is 90 cents more than the actual total.
(2) Each dime is worth 5 cents more than each nickel; each time a dime is replaced with a nickel, the total goes down by 5 cents.
(3) The number of nickels is 90/5 = 18.
(4) The number of dimes is 42-18 = 24.