Question

The barrel of a fountain pen, cylinder in shape, is $7cm$ long and $5mm$ is its diameter. A full of ink in the pen will be used when writing $310$ words on an average. How many words would use up a bottle of ink containing one-fifth of a liter.

Answer 1

Length of barrel $=7cm$, diameter $=5mm=0.5cm$

Volume of cylinder $=\pi r^{2}h$

$r=\frac{0.5}{2}=0.25cm$

$V=\frac{22}{7}\times \left(0.0625\right)\times 7=1.375ml$

Volume of in k bottle $=\frac{1}{x}\times 1000=200ml$

$1.375ml$ consumed an writing $310$ words,

words consuming in $1$ ink bottle

$=\frac{310}{1.375}\times 200$

$=4509.09$ words