An article can be bought by paying 28000 at once or by making paid 3000 and every other instalment is 100 less than previous one
Answers
Installments are as: 3000,2900.......
So to make 28000 by allowing installments we have to sum them.
By AP sum= Sn=n/2(2a+(n-1)d)
Where all symbols have usual meaning,,
We get = 28000= n/2(2*3000+(n-1)(-100))
From here you can calculate the number of months by finding value of "n" by Quadratic formulae.
Hope this is what you are searching for.
Given : An article can be bought by paying 28,000 at once or by making 12 monthly installments. If the first installment paid is * 3,000 and
every other installment is 100 less than the previous one,
To find : (i) amount of installment paid in the 9th month
(ii) total amount paid in the installment scheme.
Solution:
Complete Question : https://brainly.in/question/17699766
1st installment = Rs 3000
Next installment is 100 less than previous installment
This is an AP
a = 3000
d = - 100
9th installment = a + (9-1)d = a + 8d = 3000 + 8(-100)
= 3000 - 800
= 2200 Rs
12th installment = a + 11d = 3000 -1100 = Rs 1900
Amount paid in 12 installments = (12/2)(3000 + 1900)
= 6 * 4900
= 29400 Rs
total amount paid in the installment scheme. = Rs 29400
amount of installment paid in the 9th month = Rs 2200
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