1. The amount of money a family spends on food varies directly as their income. A family making $32,000 a year will spend $8,000 on food. How much would a family earning $52,000 spend on food?
2. The current in an electrical circuit varies inversely as the resistance. The current is 15 amps when the resistance is 40 ohms. Find the current when the resistance is 30 ohms.
3. The square of a number is 30 less than 11 times the number. Find the number.
4. The square of a number is the same as 5 times the number. Find the number.
5. If twice a number is subtracted from the square of a number, the result is 48. Find the number.
6. If the square of a number is increased by 42, the result is the same as 13 times the number. Find the number.
7. The square of 2 more than a number is the same as 10 more than 9 times the number. Find the number.