Three friends say they are friends A,B and C and they want to buy a teacher a gift so they each put in $10($30 total) and a four
th friend say he is friend D and uses the money and buys a $25 gift and has $5 left and gives each of the three friends $1 back so they technically used $9 each but 9x3=27 and there is $2 left from the $5 but 27+2=29 so when is the last dollar like how does this work?
If the thing bought was 25 dollars, then each one of A B and C put in 25/3 = 8.3333 dollars. If 1 dollar each was going back, then the sum became 9 1/3 dollars. 3 * 9 1/3 = 27 + 1 = 28. There is 2 dollars left. Everything is fine.
25 + 3 = 28
The three each got 1 dollar back. But the total accounted for is 25 + 3 = 28
There's 2 left over. That makes 30. Everything's fine. There is no missing dollar.
All you have to do is multiply the top and bottom by the same number (I'll do two). 5 times 2 = 10, and 8 times 2 = 16. 10/16 is equivalent to 5/8. A proportion for this can be written as 5/8 = 10/16.
