Question

an elastic which is 72cm long,is stretched to 90m .Fin the percentage increase in its length

Answer 1

increment in the length= 90-72=18cm
hence ℅ increase = 18×100/72= 25℅

Answer 2

Step-by-step explanation:

Answer:

Original = 72 cm

Stretched = 90 cm

Percentage Increase = ?

$\underline{\bigstar\:\textsf{According to the given Question :}}$

$:\implies\sf Increase\%=\dfrac{Change}{Original} \times 100\\\\\\:\implies\sf Increase\%=\dfrac{Stretched-Original}{Original} \times 100\\\\\\:\implies\sf Increase\%=\dfrac{90 \:cm - 72\:cm}{72 \:cm} \times 100\\\\\\:\implies\sf Increase\%=\dfrac{18\:cm}{72 \:cm} \times 100\\\\\\:\implies\sf Increase\%= \dfrac{1}{4} \times 100\\\\\\:\implies\underline{\boxed{\sf Increase\%=25\%}}$

⠀

$\therefore\:\underline{\textsf{Percentage Increase in length is \textbf{25\%}}}.$