My nieces birthday was a week ago if I gave her a $20 twenty dollar , my mother quadripples that ammount, not only that, but her mother tripples that ammount. By The time she went home she knew she had a lot of money, but how much excaly did she have? with the $20, mother quaddripling this ammount and her mother trippling it. How much money does my niece have all together.
If you take the first $20 dollars and, like your problem says, you "quadripple" the $20, what you are doing is adding four times the additional amount. You can do this either by adding, or by multiplying 20 X4, which would make $80 dollars (20+20+20+20).
Those $80 dollars, according to your problem, are then trippled. This means that there is three times the original amount. For this you either add or multiply 80 X3 (80 + 80 + 80) which equals $240. Hence, your niece will have a total of $240.00 at the end.