It is not a sum, it is a product.
3 times x = 24 (write equation)
3x = 24 (isolate x by dividing the coefficient, 3, on both sides)
/3 /3
x = 8 (this i your answer)
Therefore 3 times 8 gives you 24.
Say that you're thinking of number 
You multiply it by 8, and have 
You add -1 (i.e., you subtract 1) and have 
This equals -17, so you have

Add 1 to both sides

Divide both sides by 8:

So, you were thinking of -2.
t=2w-1
OPTION A is the correct answer...
Answer: 2.50 dollars
Explanation:
Locate 5 on the x axis, which corresponds to buying 5 kgs of apples.
Draw a vertical line through 5 on the x axis until you reach the blue line. Mark this as point P.
From point P, draw a horizontal line until you reach the y axis. You should arrive at y = 2.5
This tells us that buying x = 5 kgs of apples will cost a total of y = 2.50 dollars.
<h3>
Answer: 9t+8(101-t)</h3>
Work Shown:
t = number of hours tutoring
101-t = number of hours working as a waiter
The expressions t and 101-t add to 101.
9t = amount earned as a tutor, at $9 an hour
8(101-t) = amount earned as a waiter, at $8 an hour
9t+8(101-t) = total amount earned from both jobs
This does not account for taxes or other fees. Optionally, you can distribute the 8 through the (101-t) terms, then combine like terms to simplify.