Answer:
It costs $34 to buy a box of 64 markers.
Step-by-step explanation:
Check whether we are working with a direct proportion, in which case the comparison between the price and the number of markers would be the same.
$
14 ÷ 24 = $0.58 and
$
7 ÷ 10 = $
0.70
The prices differ, so they are not directly proportional.
The reason is that both prices include the price of the box, which is the same. This can be thought of as the constant.
If you were to draw a graph of price (on the y
-axis) and number of markers (on the x
-axis) you would get a straight line where the
y
-intercept would be the price of the box and the slope would be the price of a marker. (rate of change of price)
Let's find the slope.
m
=
(y
_2
−
y
_1
/x
_2
−
x
_1)
m = ($14
−$
7
/24−
10) = ($
7
/14 markers) = $
0.50
/
marker
Therefore each marker costs
$
0.50 or 50
c
the price of 64 markers is:
64 × 0.5 = $
32.00 ← this is just the markers,
How much does the box cost? Consider
$
7 for 10 markers at $
0.50 each
$
7 − 10 × $
0.50 = $
7 − $
5 = $
2
The box itself costs $2
The total cost of 64 markers in a box would be:
$
2 + $
32 = 34#
