#### Explanation:

Let's call the amount of money Sam start with $m$.

Now, taking each phrase one at a time we can build an equation for solving $m$:

He spent $4.85 on lunch so we know: m =$4.85

Plus, he bought 2 books at $7.95 each or 2 xx$7.95 so we can add to the equation:

m = $4.85 + (2 xx$7.95)

And finally, we know he had $8.20 left at the end of the day so we can add this to our equation: m =$4.85 + (2 xx $7.95) + 8.20 Now we can solve by doing the necessary arithmetic: m =$4.85 + $15.90 + 8.20 m =$20.75 + 8.20

m = \$28.95