Question

Every floor of a $104$-storey skyscraper is $4m$ high. If a balloon rises $3m$ every second ,how long will it take to rise from the ${36}^{th}$ floor to the ${96}^{th}$ floor?

Answer 1

Number of floors from $36$ to $96$ $=96-36=60$
Height of each floor $=4m$
Raising speed of balloon $=3m$ per second
Now, the total height from ${36}^{th}$ floor to ${96}^{th}$ floor
$=$ (number of floors)( height of each floor)
$=60\times 4m$
$=240m$

$\Rightarrow$ Distance between ${36}^{th}$ floor and ${96}^{th}$ floor $=240m$

We know that, Time $=$ $\frac{\text{Distance}}{\text{Speed}}$

$\Rightarrow$ Time $=$ $\frac{240m}{3m\text{per second}}$

$\Rightarrow$ Time $=$ $80$ seconds.

Hence, balloon take $80$ seconds to rise from the ${36}^{th}$ floor to the ${96}^{th}$ floor.