Question

The ratio of the number of stamps with Rahul to the number of stamps with Sahil is \[4:5\] . If Rahul has 24 stamps, how many stamps does Sahil have?

Answer 1

Hint: First, we have to assume the number of stamps of Sahil as x which we want to find. Then we have to use the ratio equals to number of stamps Rahul have to number of stamps Sahil have i.e. given as \[\dfrac{4}{5}=\dfrac{\text{stamps of Rahul}}{\text{stamps of Sahil}}\] . On solving and substituting the values, we will get the value of x as answer.

Complete step by step solution:
In the question we are given the ratio of stamps of Rahul to Sahil i.e. \[4:5\] . Also, Rahul has 24 stamps, so we have to find the number of stamps Sahil has.
So, here we will use the ratio equals the number of stamps Rahul has and the number of stamps Sahil has. So, assuming the number of stamps of Sahil as x. In mathematical form, we can write is as
\[\dfrac{4}{5}=\dfrac{\text{stamps of Rahul}}{\text{stamps of Sahil}}\]
Now, here we will substitute stamps of Sahil as x and that of Rahul as 24 which is given to us. So, we will get
\[\dfrac{4}{5}=\dfrac{24}{x}\]
Now, making x as variable of LHS and all the constant term on RHS we will get as
\[x=\dfrac{24\times 5}{4}=30\]
Thus, we get a value of x as 30 which is basically the number of stamps of Sahil.
Hence, Sahil has 30 stamps.

Note: Generally, in this type of problem we must have to do verification of the answer we got on solving i.e. we have to find the ratio of stamps of Rahul to stamps of Sahil and then check whether we are getting the same ratio as that given in question. So, on doing this we will get
\[\dfrac{\text{stamps of Rahul}}{\text{stamps of Sahil}}=\dfrac{24}{30}=\dfrac{4}{5}\]
Thus, we get the same ratio, so our answer is correct. One common mistake which might happen is taking x as subject variable and then solving i.e. \[x=\dfrac{24\times 4}{5}=19.2\] which is incorrect instead of writing \[x=\dfrac{24\times 5}{4}=30\] . So, do not make this type of mistake.