there are 84 quarters lined up. You start at the beginning, replacing every 2nd coin with a dime. Then you go to the beginning of the line and replace every third coin with a nickel. Then you start at the beginning and replace every fourth coin with a penny. How much is this row of coins worth in cents?
Let's see: you start with 84 quarters.
Now you change every 2nd quarter with a dime; so you now have 42 quarters (those in odd-numbered locations) and 42 dimes (those in even numbered locations).
When you change every third coin with a nickel, half of them will come from odd-numbered locations and half will come from even-numbered locations. Since 84 divided by 3 is 28, 14 nickels will be in odd-numbered locations and 14 will be in even numbered locations. You now have 28 quarters and 14 nickels in odd-numbered locations and 28 dimes and 14 nickels in even-numbered locations.
Changing every fourth coin with a penny, will place 21 pennies, all in even-numbered locations; 14 in locations that have dimes and 7 in locations that have nickels.
In odd-numbered locations, you have 28 quarters and 14 nickels; in even-numbered locations, you have 14 dimes, 14 pennies, 7 nickels and 7 pennies.
Total: 28 quarters, 14 dimes, 21 nickels, and 21 pennies
All we really need to do is to look at the first 12 coins..(the common denominator of 2, 3 and 4)....whatever pattern that exists there just repeats itself 7 times
We will have
Q D N P Q N Q P N D Q P
So we have
4 x 7 = 28 quarters
2 x 7 = 14 dimes
3 x 7 = 21 nickels and 21 pennies
The same as geno found....
I'll let you total the money....!!!! (in pennies, remember !!!)