Answer:
Yes we need to convert measurements to same unit to determine whether she purchased the right amount of ribbon or not.
Mimi purchased 5 yards of ribbon which is less than what she needed that is 5.5 yards
Explanation:
Yes we need to convert measurements to same unit to determine whether she purchased the right amount of ribbon or not.
We cannot compare two different units therefore, we are always required to convert all the measurements into a single unit for the sake of comparison.
Mimi needs eleven pieces of rhinestone ribbon.
Each piece is 18-inch long.
So the total amount of ribbon that she need is
Total amount needed = 11*18
Total amount needed = 198 inches
Convert the amount of ribbon from inches to yards
1 yard is equal to 36 inches
Total amount needed = 198/36
Total amount needed = 5.5 yards
But Mimi purchased 5 yards of ribbon which is less than what she needed that is 5.5 yards.
Buying options:
$6 per yard
$55 for whole spool
Since Mimi needs 5.5 yards or round it to nearest whole because ribbon is sold in per yard basis so 6 yards of ribbon will cost
Cost = $6*6 = $36
$36 are less than $55 therefore, it is better to buy on per yard basis rather than the whole spool of ribbon.