High School

1. A bookstore sells 5 different types of books. If each type has 12 copies and they sell 30 copies in total, how many copies of each type are left?

A. 0
B. 2
C. 6
D. 10

2. A gardener plants 8 rows of flowers. Each row has 15 flowers. If 20 flowers die, how many flowers does the gardener have left?

A. 100
B. 80
C. 60
D. 120

3. A factory produces 250 toys per hour. If it operates for 8 hours and 300 toys are defective, how many good toys are produced?

A. 1,800
B. 1,900
C. 2,000
D. 2,100

4. A car can travel 30 miles on one gallon of gas. If the car has 10 gallons and the driver uses 4 gallons for a trip, how many miles can the driver still travel?

A. 180
B. 150
C. 120
D. 300

5. A chef makes 4 batches of cookies, with each batch containing 24 cookies. If he gives away 36 cookies, how many cookies does he have left?

A. 60
B. 72
C. 48
D. 84

6. A school has 12 classes with 25 students each. If 15 students transfer to another school, how many students remain?

A. 285
B. 300
C. 275
D. 350

7. A factory produces 150 gadgets per day. If it operates for 5 days and sells 600 gadgets, how many gadgets does it have left?

A. 300
B. 600
C. 750
D. 900

8. A runner trains for a marathon by running 10 miles each day for 6 days. If she runs an extra 5 miles on the last day, how many miles does she run in total?

A. 65
B. 70
C. 75
D. 60

Answer :

Let's go through each scenario one by one:

  1. Books in the Bookstore:

    • The bookstore has 5 different types of books, each with 12 copies. This means the total number of books is [tex]5 \times 12 = 60[/tex] copies.
    • They sell 30 copies in total, so the number of copies left is [tex]60 - 30 = 30[/tex] copies.
    • Since the copies are evenly divided after sales, each type has approximately [tex]\frac{30}{5} = 6[/tex] copies left.
    • Option C: 6
  2. Flowers in the Garden:

    • There are 8 rows with 15 flowers in each, so the total number of flowers is [tex]8 \times 15 = 120[/tex] flowers.
    • After 20 flowers die, the number of flowers left is [tex]120 - 20 = 100[/tex] flowers.
    • Option A: 100
  3. Toys Produced by the Factory:

    • The factory produces 250 toys per hour and operates for 8 hours, making [tex]250 \times 8 = 2000[/tex] toys.
    • With 300 defective toys, the number of good toys is [tex]2000 - 300 = 1700[/tex], but since this isn't an option, we must have an error in reading; therefore, from given, the closest would need review based on additional options.
    • With re-check: None of provided options match considering context.
  4. Car Distance Travelled:

    • The car can travel 30 miles per gallon. With 10 gallons, it can go [tex]10 \times 30 = 300[/tex] miles.
    • After using 4 gallons, the driver has 6 gallons left. The distance the car can travel now is [tex]6 \times 30 = 180[/tex] miles.
    • Option A: 180
  5. Cookies Baked by the Chef:

    • The chef makes 4 batches, each with 24 cookies, for a total of [tex]4 \times 24 = 96[/tex] cookies.
    • After giving away 36 cookies, [tex]96 - 36 = 60[/tex] cookies are left.
    • Option A: 60
  6. Students in the School:

    • There are 12 classes with 25 students each, totaling [tex]12 \times 25 = 300[/tex] students.
    • After 15 students transfer, [tex]300 - 15 = 285[/tex] students remain.
    • Option A: 285
  7. Gadgets in the Factory:

    • Production is 150 gadgets per day, and for 5 days, it's [tex]150 \times 5 = 750[/tex] gadgets.
    • With 600 gadgets sold, [tex]750 - 600 = 150[/tex] gadgets are left.
    • Re-evaluation needed: Initial set prevents alignment.
  8. Runner's Marathon Training:

    • For 6 days she runs 10 miles each, totaling [tex]6 \times 10 = 60[/tex] miles.
    • With an extra 5 miles on the last day, she runs [tex]60 + 5 = 65[/tex] miles in total.
    • Option A: 65

Each solution process involves simple multiplication and subtraction, which is suitable for middle school students learning basic arithmetic operations.