Question

Eric gave half of the money that he had to Kevin. Eric then bought a sandwitch for $\$5$. He now has $\$20$ remaining with him. Eric had $\$$ initially.

Answer 1

Let $x$ be the amount of money (in dollars) Eric had initially.
After giving half of the money to Kevin, Eric had remaining amount$=x-\frac{x}{2}=\frac{2x}{2}-\frac{x}{2}=\frac{x}{2}$.

After buying sandwitch for $\$5$, Eric now has $\frac{x}{2}-\$5$ amount of money.
Given that Eric now has $\$20$ with him.
$\Rightarrow \frac{x}{2}-\$5=\$20$

Step I: Add $5$ on both the sides of the equation
$\Rightarrow \frac{x}{2}-\$5+\$5=\$20+\$5$

$\Rightarrow \frac{x}{2}=\$25$

Step I:Multiply by $2$ on both the sides of the equation
$\Rightarrow 2\times \frac{x}{2}=\$50\Rightarrow x=\$50$
$\therefore$ Eric had $\$50$ with him initially.