21/42 as a decimal and a percentage
21/42
= 0.5 = 50%
21/42 means 21 out of 42 equal parts. As a decimal it is 0.5, and as a percentage 50%.
Ways to write it
- Decimal
- 0.5
- Percentage
- 50%
- Simplest form
- 1/2
- As a division
- 21 ÷ 42
- Equivalent fractions
- 2/4 = 3/6 = 4/8 = 5/10
- Compared with one half
- Equal to 1/2
- Reciprocal
- 42/21
- 21/42 of 210
- 105
How to work it out
- Divide the top number by the bottom number: 21 ÷ 42 = 0.5.
- To make a percentage, multiply by 100: 0.5 × 100 = 50%.
- To simplify, divide the top and bottom by 21, their highest common factor: 21 ÷ 21 = 1 and 42 ÷ 21 = 2, so 21/42 = 1/2.
Quick check
Is 21/42 more or less than 1/2?
Show the answer
Equal to 1/2
What is 21/42 of 210?
Show the answer
105
21/42 = ?/84
Show the answer
42
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Frequently asked questions
What is 21/42 as a decimal?
21/42 as a decimal is 0.5.
What is 21/42 as a percentage?
21/42 as a percentage is 50%.
What is 21/42 in its simplest form?
21/42 in its simplest form is 1/2.