Category: Mathematics

1. If $3x-5=x+11$, then $x=$?

2. ABC works two part-time jobs. One week ABC worked 8 hours at one job, earning $\$150$, and $4.5$ hours at the other job, earning $\$90$. What were his average hourly earnings for the week?

3. For how many 3-digit whole numbers is the sum of the digits equal to 3?

4. In a cafeteria, the people are either faculty members or students. The number of faculty members is 15% of the total number of people in the cafeteria. After some of the students leave, the total number of persons remaining in the cafeteria is 50% of the original total. The number of students who left is what fractional part of the original number of students?

5. A car dealer who gives a customer a 20% discount on the list price of a car still realizes a net profit of 25% of the cost. If the dealer’s cost is $4800 what is the usual list price of the car?

6. $2000 amount is deposited into a savings account that earns interest at the rate of 10% per year, compounded semi-annually. How much money will there be in the account at the end of one year?

7. If $x+y=8$ and $2x-y=10$ then $x=$?

8. If $x=k+\frac{1}{2}=\frac{k+1}{2}$, then $x=$?

9. If $x=\frac{y}{7}$ and $7x=12$, then $y=?$

10. A certain photo state machine produces 13 copies every 10 seconds. If the machine operates without interruption, how many copies will it produce in an hour?

11. If the value of a piece of the property decreases by 10% while the tax rate on the property increases by 10%, what is the effect on the taxes?

12. If $7-x=0$, then $10-x=$?

13. In a certain population, 40% of all people have biological characteristics $X$; the others do not. if 8000 people have characteristic $X$, how many people do not have $X$?