Hey there!
[tex]\large\boxed{33.33\%}[/tex]
Find the amount he saved by finding the difference between earnings and spendings.
810 - 540 = 270
Then, find the percent 270 is of 810.
Do this by dividing 270 by 810.
270 ÷ 810 = .3333
Multiply by 100 to get the percent.
.3333 × 100 = 33.33
He saved 33.33%.
Hope this helps!