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Question
Priya earned ₹ 15,000 in the first month. Thereafter her salary increased by ₹ 1500 per year. Her expenses are ₹ 13,000 during the first year and the expenses increase by ₹ 900 per year. How long will it take for her to save ₹ 20,000 per month
Solution
Yearly Salary |
Yearly expenses |
Yearly saving |
|
1st year | 15000 | 13000 | 2000 |
2nd year | 16500 | 13900 | 2600 |
3rd year | 18000 | 14800 | 3200 |
We find that the yearly savings are in A.P. with a1 = 2000 and d = 600.
We are required to find how many years are required to save 20,000 a year …………..
an = 20,000
an = a + (n – 1)d
20000 = 2000 + (n – 1)600
(n – 1)600 = 18000
n – 1 = `18000/600` = 30
n = 31 years
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