Percentages are ratios of an amount compared to 100. The percent change of an old to new value is equal to 100% x \({ new - old \over old }\).
The total water usage for a city is 40,000 gallons each day. Of that total, 15% is for personal use and 32% is for industrial use. How many more gallons of water each day is consumed for industrial use over personal use?
| 1,600 | |
| 7,500 | |
| 2,100 | |
| 6,800 |