Question 1127229
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Here is a common sense way to solve problems like this, without the formal algebra.<br>
If all 77 coins were nickels, the total value would be 77*5 = 385 cents or $3.85.
The actual total value is $5.25, which is $1.40 (140 cents) more than $3.85.
Replacing 1 nickel with 1 dime raises the total value by 5 cents (while keeping the total number of coins the same).
The number of dimes needed to replace nickels to make up the other 140 cents is 140/5 = 28.<br>
So there are 28 dimes and 77-28 = 49 nickels.