A man spend 75% of his income. when his income is increse by 20%. He increse his expenditure 10% . By what percent are his saving increse ?
Original income= I
.25I=Savings original
.15(I*1.20)=new savings.
percent increase= (New-old)/old * 100
= (.18I-.25I)/.25I * 100
It appears his savings decreased.
To find the percent increase in savings, we first need to calculate the original savings and the new savings.
Let's assume the man's income is $100, and he spends 75% of it. So, his expenditure is 0.75 * 100 = $75.
Therefore, his savings would be 100 - 75 = $25.
Now, let's calculate the new income. Since his income is increased by 20%, we can calculate it by adding 20% (or 0.2) of the original income to the original income:
New Income = Original Income + (0.2 * Original Income) = 100 + (0.2 * 100) = $120.
To calculate the new expenditure, we need to add 10% (or 0.1) of the original expenditure to the original expenditure:
New Expenditure = Original Expenditure + (0.1 * Original Expenditure) = 75 + (0.1 * 75) = $82.50.
Now, let's calculate the new savings:
New Savings = New Income - New Expenditure = 120 - 82.50 = $37.50.
To find the percentage increase in savings, we need to calculate the difference between the new and original savings, and then divide it by the original savings. Finally, we multiply the result by 100 to get the percentage:
Percentage Increase = ((New Savings - Original Savings) / Original Savings) * 100
= ((37.50 - 25) / 25) * 100
= (12.50 / 25) * 100
= 0.50 * 100
= 50%.
Therefore, the man's savings have increased by 50%.