Answer:
31.7%
Explanation:
Here we are given that
Sarah Earns E = $3120
Sarah Spend S = $2130
Therefore Sarah Saves
Earning - expenses
E-S
=$3120-$2130
= $990
Now we have to find the percentage of this amount on his earning . In order to find the percentage we use following formula.




Hence Sarah makes 31.7% saving out of her total earnings of the month.