As a prize for winning the archery contest, I received 10 coins distributed as follows: 3 pouches, each with an equal number of coins per pouch, and four coins. I wanted to see how many coins were in each pouch without opening them, so I subtracted 4 from my total of 10 so I had six. I divided 6 by three (six coins into three pouches) and presto! 2 coins per pouch.
Let p be pouches 3p + 4 = 10 -4 -4 3p = 6 /3 /3 p = 2
We can also use the equation to find out how many coins are in a bag.