# Week 5: Division – Answers

Week 5: Division – Day 5

Three digit numbers by one digit numbers

Try to do these problems without pencil and paper.

1. What is 200 / 5 ?

200 / 5 = 10 x 20 / 5 = 10 x (20/5) = 10 x 4 = 40

2. What is 888 / 4 ?

222

3. What is 180 / 9 ?

20

4. What is 633 / 3 ?

211

5. What is 248 / 8 ?

Note that 240/8 = 30.

So 248/8 = 31.

Week 5: Division – Day 4

Three digit numbers by two digit numbers

Try to work out these divisions without pencil and paper.

1. What is 360 / 12 ?

360 = 36 x 10, therefore:

360 / 12 = 10 x 36 / 12 = 10 x 3 = 30.

2. What is 121 / 11 ?

121 / 11 = 11

3. What is 200 / 40 ?

Use the idea that 20 = 4 x 5.

200 / 40 = 10 x 20 / 10 x 4 = 20 / 4 = 5

You can directly “cancel out” zeros:

200/40 = 20/4

4. What is 560 / 70 ?

By “canceling zeros” 560/70 = 56 / 7 = 8.

5. What is 560 / 14 ?

Use the idea of finding the factors of the numerator and the denominator.

560 / 14 = (10 x 8 x 7) / (2 x 7) = (10 x 8) / 2 = 10 x 4 = 40

Week 5: Division – Day 3

1. Effie runs 8 miles in 2 hours. What is her average speed?

Speed is the number of miles per hour. 8 miles divided by 2 hours is 4 miles per hour.

2. Six friends play hockey together after school. Their ages are 9, 12, 10, 11, 15, and 9. What is the average age of people on the team?

The average age of the 6 players is: (9 + 12 + 10 + 11 + 15 + 9) / 6 = 11.

3. A group of fourteen squirrels has found a pile of 42 nuts. They decide to share the nuts equally among themselves. How many nuts does each squirrel get?

42 / 14 = 3. Each squirrel gets 3 nuts.

4. What is the probability that you will roll a 3 or a 5 on a six-sided die ?

There are 6 possibilities when you roll a six-sided die: 1, 2, 3, 4, 5, 6. The probability of rolling 3 is 1/6, and the probability of rolling 5 is 1/6. The probability of rolling one or the other is 1/6 + 1/6, which is 1/3.

5. The area of Harry’s rectangular swimming pool is 200 square meters. The width of the pool is 8 meters. What is the length of the pool?

The area of the pool is the width multiplied by the length. So the length is the area divided by the width. The length is 200 / 8 = 25 meters.

Week 5: Division – Day 2

1. What is 24 / 12?

2

2. What is 36 / 18?

2

3. What is 45 / 15?

3

4. What is 80 / 10?

8

5. What is 28 / 14?

2

Week 5: Division – Day 1

1. What is 24 / 6?

4

2. What is 36 / 9?

4

3. What is 48 / 8?

6

4. What is 63 / 7?

9

5. What is 88 / 8?

11