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Renu Spends 68% of her income. When her income increases by 40 and expenditure by 30%. Her saving is?

In this post, we are going to solve a math question which is very important for CHSL, CGL, SSC GD, SBI PO, IBPS etc.

Q. Renu Spends 68% of her income. When her income increases by 40 and expenditure by 30%. Her saving is?

Sol. 
Step-by-Step 
Step1: Assume that Renu's original income = 100

  • Her original expenditure = 68 of 100 = 68
  • Her original saving = 100 - 68 = 32
Step2: After 40% increase in income
  • New income = 140
Step3: After 30% increase expenditure
  • New expenditure = 30 of 68 = 20.4
Step4: Calculate new saving:
  • New saving = New income + New expenditure = 140-88.4 =51.6
Step5: Increase in savings:
  • Increase in saving = New saving - original saving = 51.6 - 32 = 19.6
Step6: Percentage increase in saving:
  • Percentage increase = Increase in saving/Original saving * 100
  • Percentage increase = 19.6/32 * 100 = 61.25
Therefore, the Renu saves 61.25%.

Below is the Youtube video where you can easily understand this question also.

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