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Algebra Difficulty 1.1 Junior Find the answer Canada

Which of the following numbers is less than $\frac{1}{20}$ ?

$\frac{1}{15}$
$\frac{1}{25}$
$0.5$
$0.055$
$\frac{1}{10}$

Your answer

A number or a short expression. Fractions can be typed as 3/2, and spacing doesn't matter.

Solution

If $0<a<20$ , then $\dfrac{1}{a} > \dfrac{1}{20}$ . Therefore, $\dfrac{1}{15} > \dfrac{1}{20}$ and $\dfrac{1}{10} > \dfrac{1}{20}$ .

Also, $\dfrac{1}{20} = 0.05$ which is less than both 0.5 and 0.055.

Lastly, $\dfrac{1}{20} > \dfrac{1}{25}$ since $0 < 20 < 25$ .

Therefore, $\dfrac{1}{25}$ is the only one of the choices that is less than $\dfrac{1}{20}$ .

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Source: CEMC, University of Waterloo, licensed CC-BY-NC-4.0. Statement reproduced verbatim; metadata (topic, difficulty) added by this project.