Terminating Decimal/Examples/0.625

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Example of Terminating Decimal

The number $\dfrac 5 8$ can be expressed as a terminating decimal:

$\dfrac 5 8 = 0 \cdotp 625$


Proof

\(\ds 0 \cdotp 625\) \(=\) \(\ds \dfrac 6 {10} + \dfrac 2 {100} + \dfrac 5 {1000}\)
\(\ds \) \(=\) \(\ds \dfrac {600} {100} + \dfrac {20} {100} + \dfrac 5 {1000}\)
\(\ds \) \(=\) \(\ds \dfrac {600 + 20 + 5} {1000}\)
\(\ds \) \(=\) \(\ds \dfrac {625} {1000}\)
\(\ds \) \(=\) \(\ds \dfrac {5 \times 5^3} {8 \times 5^3}\)
\(\ds \) \(=\) \(\ds \dfrac 5 8\)

$\blacksquare$


Sources