Answer:
Step-by-step explanation:
So the ratio is 5:4:2
there are 11 parts to this ratio (5+4+2)
the 5 is for the $2, the 4 is for the $1 and the 2 is for the 50 cents
he has 30 of the 50 cents
so you divide 30 by 2 to get one part of this ratio
1 part of this ratio is equal to 15 coins
multiply 15 by 5 to get the number of $2 coins: 75
multiply 15 by 4 to get the number of $1 coins: 60
add all of those parts together
30+60+75 = 165
If he uses a $1 coin to buy the sundae he will have 75 $2 coins and 59 $1 coins left
however, if he uses two 50 cents coins to buy the sundae he will have 75 $2 coins and 60 $1 coins left
