A certain shampoo is available in two sizes. A 14.2 -ounce bottle costs 3.98$ . A 33.9 -ounce bottle costs 9.98$ . Find the unit price for each size. Then state which size is the better buy based on the unit price.

Round your answers to the nearest cent.

14.2 ounce for $3.98 is more cheaper

Step-by-step explanation:

unit price formula; cost ÷ quantity

3.98 / 14.2 = 0.2802816901408

9.98 / 33.9 = 0.2943952802359

round answers to the nearest hundredth;

$0.28

$0.29

compare the answers

both equations and proportions are better.

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18