Question

Explain how you know 21/100 is grater then 1/5

Answer 1

Method 1

Assume the fractions are equal for now.

21/100 = 1/5

21*5 = 100*1 .... cross multiplication

105 = 100

The two sides are different numbers, so the original fractions aren't equal. We can fix the error by replacing each equal sign with a "greater than" sign as shown below.

21/100 > 1/5

21*5 > 100*1 .... cross multiplication

105 > 100

Think of it like working backwards up the chain.

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Method 2

Use a calculator or long division to find the following decimal values

• 21/100 = 0.21
• 1/5 = 0.20

We see that the first result is slightly larger. We can think of it like saying 21 is larger than 20.

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Method 3

To compare fractions, we need the denominators to be the same.

Let's convert 1/5 into a fraction with a denominator of 100. To do so, we multiply top and bottom by 20

1/5 = (1*20)/(5*20) = 20/100

In short,

1/5 = 2/100

When comparing 21/100 with 1/5, we're really comparing 21/100 with 20/100. We see that 21/100 is larger than 20/100 since 21 > 20.

So that is why 21/100 is greater than 1/5.

Answer 2

Explanation:

Multiply the numerator and denominator of 1/5 by 20:

`(1 * 20)/(5 * 20) = (20)/(100)`

1/5 = 20/100

Since 21/100 is greater than 20/100, then 21/100 is also greater than 1/5.