90 + 12/5 x 60=90 + 144 +100= 334
so 334 would be your answer
You calculate the markup or markdown in absolute terms (you find by how much the quantity changed), and then you calculate the percent change relative to the original value. So they're really just another form of "increase - decrease" exercises.
Example:
A computer software retailer used a markup rate of 40%. Find the selling price of a computer game that cost the retailer $25.
The markup is 40% of the $25 cost, so the markup is:
(0.40)(25) = 10
Then the selling price, being the cost plus markup, is:
25 + 10 = 35
The item sold for $35.
J. -8 is the correct answer
Label the 3 distinct sides of the box. I arbitrarily chose the letters a, b and c.
Use the info about areas as follows:
ab=54 in^2
ac=90 in^2
bc=60 in^2
Here you have 3 equations in 3 unknowns (a, b and c), which is enough info to use to determine a, b and c. Then the volume of the box is a*b*c.
Example: bc = 90, but c = 60/b. You could subst. 60/b for c in the 2nd and 3rd equation, which will eliminate c completely and leave you with 2 equations in 2 unknowns.
Continuing this procedure, I determined that a=9, b=6 and c=10. Thus, the volume of the box is V = 9*6*10 = 540 cubic inches (answer)
