You collect stamps. You give steven 21 stamps. At the end youbhave 3. How many stamps did you start

[math_celebrity]

You collect stamps. You give steven 21 stamps. At the end youbhave 3. How many stamps did you start with?

You start with s stamps.
s

You give Steven 21. Giving means you subtract from your total:
s - 21

You have 3 left
s - 21 = 3

To solve this equation for s, we type it in our math engine and we get:
s = 24