Question

What is the value of x in the equation below?

One-third (12 x minus 24) = 16

Carina spent a total of $5.27 buying a pineapple for $3.40 and some tomatoes that were on sale for $0.85 per pound. To determine the number of pounds of tomatoes that she bought, x, Carina wrote and solved the equation as shown below.


3.40 + 0.85 x = 5.27. 0.85 x = 8.67. x = 10.2 pounds.


Where, if anywhere, did Carina make an error?

Answer 1

The value of x in the given equation, One-third (12 x minus 24) = 16 can be calculated as shown below;We have the equation;One-third (12x - 24) = 16Dividing both sides of the equation by one-third;1/3 x (12x - 24) = 16Multiplying both sides of the equation by 3 to eliminate the fraction;3 x 1/3 x (12x - 24) = 3 x 16Simplifying;4x - 8 = 48Adding 8 on both sides of the equation;4x - 8 + 8 = 48 + 8Simplifying;4x = 56Dividing both sides by 4;x = 14Therefore, the value of x in the equation; One-third (12 x minus 24) = 16 is 14.While determining the number of pounds of tomatoes that she bought, Carina made an error. The equation is written correctly as;3.40 + 0.85 x = 5.27Multiplying 0.85 on both sides of the equation;0.85 x 3.40 + 0.85 x 0.85x = 5.27 x 0.85Simplifying;2.89 + 0.7225 x = 4.4745Subtracting 2.89 on both sides;0.7225 x = 1.5845Dividing both sides by 0.7225;x = 2.19However, Carina made a mistake by rounding off 10.2 to 10.