A salesman is allowed 5% commission on the total sales made by him plus a bonus of 1% on the excess of his sale over Rs. 20000. If the total earning is Rs. 1450 on commission alone, then find his total earnings?
(a) Rs. 100
(b) Rs. 90
(c) Rs. 80
(d) Rs. 110

Hint: First, before proceeding for this, we are not given with the value of total sales and let us suppose it be as Rs. x. Then, by using the condition given in the question that Rs. 1450 is the 5% of the total sales which is assumed x is given by 5% of x=1450. Then, we need to calculate the excess sold by him by subtracting the amount Rs 20000 from the actual sale amount which is Rs. 29000 and then by using the condition given in the question, we get the desired answer.

Complete step-by-step answer:
In this question, we are supposed to find the total earning of the salesman when he salesman is allowed 5% commission on the total sales made by him plus a bonus of 1% on the excess of his sale over Rs. 20000 and the total earning is Rs. 1450 on commission alone.
So, before proceeding for this, we are not given with the value of total sales and let us suppose it be as Rs. x.
Then, by using the condition given in the question that Rs. 1450 is the 5% of the total sales which is assumed x is given by:
5% of x=1450
Then by solving the above expression, we get the value of x which is total sales as:
$\begin{align}
  & \dfrac{5}{100}\times x=1450 \\
 & \Rightarrow x=\dfrac{1450\times 100}{5} \\
 & \Rightarrow x=29000 \\
\end{align}$
So, we get the total sales as Rs. 29000.
Now, we are also given in the question that the earning of the salesman is only 1% of the excess he sold above Rs 20000.
So, we need to calculate the excess sold by him by subtracting the amount Rs 20000 from the actual sale amount which is Rs. 29000 as:
Excess=29000-20000
Excess=9000
So, we get the excess amount sold by him as Rs. 9000.
Now, we are asked to find the value of the total earning by the salesman which is given by the formula as:
1% of excess amount
Now, by substituting the value of excess amount in above expression, we get the total earning as:
$\dfrac{1}{100}\times 9000=90$
So, we get the total earnings of the salesman as Rs. 90.

So, the correct answer is “Option (b)”.

Note: Now, to solve these types of the questions we need to be careful with the conditions given in the question as the total earning is the amount earned by the salesman on the excess from the 20000 amount and not the 1% of the actual sale amount. If we don’t pay attention to the given condition then we will surely get a wrong answer.