Question

If a pipe fills 6 oil tankers in 4.5 hours. How much time does it take to fill 4 such oil tankers?

Answer 1

Hint: Suppose we require 10 boxes to pack 50 chocolates then how many boxes are required to pack 40 chocolates.
First, we will see that 50 chocolates require 10 boxes which implies how many chocolates are there in 1 box i.e. 5 chocolates.
Similarly, if we have number of chocolates in 1 box then we can calculate the number of
box required to pack 40 chocolates i.e. if 5 chocolates are packed in 1 box, then chocolates in 2 boxes, similarly 15 in 3 and so on till we reach at 40.
So, 40 chocolates require 8 boxes.

Complete step-by-step answer:
In this given manner we can solve the given question.
That is if 6 tanks require 4.5 hours to fill in then 4 tanks requires how much time?
$ \Rightarrow 6 \leftrightarrow 4.5$hrs
$ \Rightarrow 4 \leftrightarrow ?$
First calculate time required by 1 tanker to fill in i.e.
 $
   \Rightarrow 6 \leftrightarrow 4.5hrs \\
   \Rightarrow 1 \leftrightarrow \dfrac{{4.5}}{6}hrs \\
   \Rightarrow 1 \leftrightarrow \dfrac{3}{4}hrs \\
$
 Now we have time required to fill in 1 oil tanker i.e. $\dfrac{3}{4}$hrs or 45 minutes.
So, time required to fill 4 tankers i.e.
 $
   \Rightarrow 4 \leftrightarrow \dfrac{3}{4} + \dfrac{3}{4} + \dfrac{3}{4} + \dfrac{3}{4} = \dfrac{{12}}{4} = 3hrs \\
   \Rightarrow 4 \leftrightarrow 3hrs \\
$
So, the time required to fill 4 tankers is 3 hours.

Note: This can be solved by ratio method also i.e.
$ \Rightarrow \dfrac{{4.5}}{6} = \dfrac{x}{4}$
Where x is the time taken by the pipe to fill 4 such oil tankers.
 $
   \Rightarrow \dfrac{{4.5}}{6} = \dfrac{x}{4} \\
   \Rightarrow \dfrac{{45}}{{60}} = \dfrac{x}{4} \\
   \Rightarrow x = \dfrac{{45 \times 4}}{{60}} \\
   \Rightarrow x = 3hrs \\
$