Answer:
1%
Explanation:
Money spent by the stationer :
- 100 books x 80 rupees
- 8000 rupees
Money earned (after donation and sales) :
- Donated 10 books = 0 rupees
- Sold rest at 88 rupees per book
- 90 books x 88 rupees
- 7920 rupees
Here, the money spent is more than the money earned. Hence, we have to find the loss percentage.
- Loss % = New - Old / Old
- Loss % = 7920 - 8000 / 8000
- Loss % = -80/8000
- Loss % = -1/100
The loss percentage is 1%