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A vending machine has $6.30 in it. There are 52 coins total and the machine only accepts nickels,
dimes, and quarters. There are five more dimes than nickels. How many of each coin are in the machine ?
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It is a typical problem to be solved using only one single unknown and only one single equation.
Let x be the number of nickels.
Then the number of dimes is (x+5), according to the condition.
The quarters are the rest coins, and their number is (52-x-(x+5)) = (47-2x).
Having it, you write the total money equation
5x + 10(x+5) + 25*(47-2x) = 630 cents.
Simplify and solve
5x + 10x + 50 + 25*47 - 50x = 630
-35x = 630 - 50 - 25*47 = -595
x = = 17.
ANSWER. 17 nickels, 22 dimes and the rest 52 - 17-22 = 13 coins are quaters.
CHECK. 17*5 + 22*10 + 13*25 = 630 cents, in total. ! Correct !
Solved.
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It is how this problem is intended and is expected to be solved.
Only the persons UNFAMILIAR with a standard basic mathematical education principles,
like @josgarithmetic or @Penguin, may think differently . . .