Question

express 7/80 in decimal expression without dividing it actually. ​

Answer 1

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Represent $\frac{7}{80}$ as decimal expression without dividing it actually.

${\huge\star{\mathfrak{\underline{\underline{Answer:}}}}}$

On prime factorising the denominator, 80.

we get,

80 = 2×2×2×2×5 = ${2}^{4}\times 5$

we know that to make the number divisible by 10 we need ${2}^{n} \: and \: {5}^{n}$

so, multiplying numerator and denominator 5³.

$\implies \frac{7 \times {5}^{3} }{80 \times {5}^{3} }$

$\frac{875} {10,000}$

= 0.0875