a)
Add the costs of material and labor together:
[tex] 3.38 + 5.57 = 8.95 [/tex]
Subtract this value from how much Lucy sells a necklace for:
[tex] 15.99 - 8.95 = 7.04 [/tex]
Lucy's profit from a necklace is $7.04.
Set up a fraction where the profit is the numerator, and the sale price is the denominator to get your ratio:
[tex] \frac{7.04}{15.99} = \frac{704}{1599}[/tex]
The ratio will be 704/1599.
b)
Divide the profit by the sale price:
[tex] 7.04 \div 15.99 = 0.4403 [/tex]
Multiply the decimal by 100 to get your percentage:
[tex] 0.4403 \times 100 = 44.03 [/tex]
Check the tenths value to round to the nearest percent:
0 < 5
44.03 ≈ 44
44% of the sale price is profit.
c)
Divide the total amount Lucy earned at the fair by the sale price of an individual necklace:
[tex] 223.86 \div 15.99 = 14 [/tex]
Lucy made 14 necklaces.
To find the total profit Lucy made from the fair, multiply the total amount of necklaces she made by the profit for each necklace:
[tex] 14 \times 7.04 = \boxed{98.56} [/tex]
Lucy's total profits were $98.56.