Sari has 3 times as many pencil erasers Sam. Together, they have 28 erasers. How many erasers does Sari have

To solve this problem we can use equation.

If we say that x is number of Sams pencils we can say too that Sari has 3x (because she has 3 times more)

And we know that together they has 28 pencils.

x+3x=28

4x=28 / : 4 (divide both sides by 4)

x=7

Sam has 7 pencils.

We know that Sari has 3 times more so 7*3=21 - its the result.

The answer to your question is Sari has twenty-one erasers.