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Solution - Ramkali required Rs 2,500 after 12 weeks to send her daughter to school. She saved Rs 100 in the first week and increased her weekly saving by Rs 20 every week. Find whether she will be able to send her daughter to school after 12 weeks. - CBSE Class 10 - Mathematics

ConceptSum of First n Terms of an AP

Question

Ramkali required Rs 2,500 after 12 weeks to send her daughter to school. She saved Rs 100 in the first week and increased her weekly saving by Rs 20 every week. Find whether she will be able to send her daughter to school after 12 weeks.

What value is generated in the above situation?

Solution

 

Since Ramkali increased her weekly savings uniformly every week by a fixed number, her savings will form an AP.

Let Sn be the sum of savings in all 12 weeks.

`:.S_n=n/2[2a+(n-1)d]`  (Here, a is the money saved in the first week and d is the fixed increase in the weekly savings.)

`=>S_n=12/2[2xx100+(12-1)20]`

= Rs 2520

Ramkali required Rs 2,500 after 12 weeks, but she saved Rs 2,520. So, she will be able to send her daughter to school after 12 weeks.

It shows that Ramkali is aware of the importance of girl child education

 
Is there an error in this question or solution?

APPEARS IN

2014-2015 (March) Delhi Set 1
Question 22 | 4 marks
2014-2015 (March) Delhi Set 2
Question 23 | 4 marks
2014-2015 (March) Delhi Set 3
Question 24 | 4 marks

Reference Material

Solution for question: Ramkali required Rs 2,500 after 12 weeks to send her daughter to school. She saved Rs 100 in the first week and increased her weekly saving by Rs 20 every week. Find whether she will be able to send her daughter to school after 12 weeks. concept: Sum of First n Terms of an AP. For the course CBSE
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