# A soft drink costs $1.65, and each refill for the drink costs 0.95. If you have$4.50, how many refills can you purchase?

Nov 11, 2016

There are 3 refills

#### Explanation:

$\textcolor{p u r p \le}{\text{The trick with algebra is to aske yourself: how would I do this with just numbers.}}$$\textcolor{p u r p \le}{\text{Then put in letters for the unknown values.}}$

$\textcolor{g r e e n}{\text{initial cost + total refill cost = total cost}}$

$\textcolor{p u r p \le}{\text{Let the count of refills be } r}$
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=> color(brown)($1.65+r$0.95=$4.50) Dropping the dollar sign and subtracting $\textcolor{b l u e}{1.65}$from both sides we have: $\textcolor{b r o w n}{1.65 \textcolor{b l u e}{- 1.65} + r 0.95 = 4.50 \textcolor{b l u e}{- 1.65}}$$0 + r 0.95 = 2.85$Divide both sides by 0.95 $r \times \frac{0.95}{0.95} = \frac{2.85}{0.95}$But $\frac{0.95}{0.95} = 1$giving $r = \frac{2.85}{0.95} = 3\$

So there are 3 refills