# Question #c5d4c

Oct 27, 2017

You got a and b right, so let's move on

#### Explanation:

c) Cost of the pencils=price times number: $.25 \left(x + 10\right)$

d) Total cost is $.50 x + .25 \left(x + 10\right) = .50 x + .25 x + 2.50$

The inequality is:
$.75 x + 2.50 < 5.00$

Subtract $2.50$ from both sides:
$.75 x < 2.50$

Divide both sides by $.75$:
$x < 3.33$

Since $x$ must be whole, this translates to $x \le 3$

Answer: at most she bought 3 pens and 13 pencils.

Check:
$.50 \cdot 3 + .25 \cdot 13 = 4.75$ this will do
$.50 \cdot 4 + .25 \cdot 14 = 5.50$ this is too expensive