If they are proportional, then y/x should always be the same.
So 9/2= 4.5
We need to find the y value at x=3 to make y/x equal 4.5
4.5 = y/3
y = 4.5*3 = 13.5
78 rounded to the nearest tenth is 80
Markup = $4
b) markup as a percentage of cost is 33.3%
Step-by-step explanation:
Markup
markup = selling price - cost
= $13 - 9
... markup = $3
Markup as a Percentage of Cost
To find the percent markup, divide the markup by the reference value and multiply the ratio by 100%. The reference value for markup is usually cost price, but sometimes may be selling price.
... markup / cost × 100% = 3/9×100% = 33 1/3% ≈ 33.3%
I think the answer is 0.3