Question

In 2008, Hansi earned 7800. He earned $15\% $ more in 2009. Calculate how much he earned in 2009.

Answer 1

Hint:
We can find the increase in the amount he earned in 2009 by finding the given percentage of the amount he earned in the year 2008. Then we add the increase in the earning with the earing in 2008. This sum will give the required amount he earned in 2009.

Complete step by step solution:
We are given that the amount Hansi earned is $\$ 7800$.
It is also given that he earned $15 \% $ more in 2009.
So, the amount of money he earned in 2009 is given by $15 \% $ of the money earned in 2008.
So, it is given by,
 $I = 7800 \times 15\% $
We can convert the percentage into fraction.
 $ \Rightarrow I = 7800 \times \dfrac{{15}}{{100}}$
On cancelling the zeros, we get,
 $ \Rightarrow I = 78 \times 15$
After doing the multiplication, we get,
 $ \Rightarrow I = 1170$
Thus, he will earn 1170 more in the year 2009.
We can find the amount he earned in 2009 by adding it with the money he earned in 2008.
 $ \Rightarrow {A_{2009}} = 7800 + 1170$
 $ \Rightarrow {A_{2009}} = 8970$

So, the amount earned by Hansi in the year 2009 is 8970.

Note:
Alternate solution to this problem is given by proportionality,
It is given that Hansi earned 7800 (dollar) in 2008. Let it be $100\% $ .
 We can write it as,
 $7800 = 100\% $ …. (a)
Then it is given that he earned $15\% $ more in 2009.
Let the amount he earned be x. Then we can write x as follows,
 $x = 100\% + 15\% $
 $ \Rightarrow x = 115\% $ …. (b)
Now we divide equation (a) with (b).
 $ \Rightarrow \dfrac{x}{{7800}} = \dfrac{{115\% }}{{100\% }}$
Now we can cancel the percentage,
 $ \Rightarrow \dfrac{x}{{7800}} = \dfrac{{115}}{{100}}$
On cross multiplication we get,
 $ \Rightarrow x = \dfrac{{115}}{{100}} \times 7800$
On cancelling the zeros, we get,
 $ \Rightarrow x = 115 \times 78 $
After doing the multiplication, we get,
 \[ \Rightarrow \] x=8970
So, the amount earned by Hansi in the year 2009 is 8970.