Multiples

Multiples are numbers that result from multiplying a given number by an integer. For example, the even integers 2, 4, 6, 8, 10, \dots are multiples of 2 because they are the products of 2 and another integer.

The integers 3, 6, 9, 12, 15, 18, 21, \dots are multiples of 3.

The integers 5, 10, 15, 20, 25, 30, \dots are multiples of 5.

To find the multiples of a number, simply multiply it by different whole numbers.

Examples

1. A train travels at an average speed of 200 km/h. How far can it travel in 2 hours?

In 1 hour, the train travels 200 km, so in 2 hours, it travels 2 \times 2002 \times 200 km, which is 400 km.

2. If Alan can eat a burger in 20 minutes, how long would it take him to eat 3 burgers, assuming he eats them all at the same rate?

For 1 burger, it takes 20 minutes, so for 3 burgers, it takes 3 \times 203 \times 20 minutes, which is 60 minutes or 1 hour.

3. Gina can sew a piece of cloth in 36 minutes. How long will it take her to sew 20 similar pieces of cloth, assuming she sews all pieces at the same rate?

For 1 piece of cloth, it takes 36 minutes, so for 20 pieces, it takes 36 \times 2036 \times 20 minutes, which is 720 minutes or 12 hours.

4. A wolf can eat a rabbit in 15 minutes. How long will it take 3 wolves to eat a rabbit, assuming they all eat at the same rate?

Since there are three wolves eating the rabbit, they will take less time. It would take \frac{15}{3}\frac{15}{3} minutes, which is 5 minutes.

5. David can tend to a garden in 2 hours. How long will it take him to tend to 5 similar gardens, assuming he works at the same rate?

For 1 garden, it takes 2 hours, so for 5 gardens, it takes 2 \times 52 \times 5 hours, which is 10 hours.

6. Five men can tend to a garden in 12 hours. How long will it take one man to tend to the same garden, assuming the men work at the same rate?

Since one man will take longer to tend to the garden, it would take 12 \times 512 \times 5 hours, which is 60 hours, or 2.5 days.

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