Question

Frieend please tell me the formula for this question----.

From the household expenses, A student saves rupees 5 in the first week, rupees 10 in second week, rupees 15 third week and so on. Then how much money he has saved after 15 week.



if you want to solve this question you can solve, but please write the formula in a separate box​

Answer 1

Answer:

he has saved 600 rupees after 15 weeks

Explanation:

because every week he saves 5 rupees more than the previous week so in 15th week he will save 15×5 75 rupees

and according to question we have to find total money he saved so we have to add money saved by him in all weeks so 5+10+15+20+25+30+35+40+45+50+55+60+65+70+75=600

so sanswer is 600

Answer 2

Answer:

the formula is Tn=a+(n-1)d

Explanation:

where Tn is nth term (term to be find )

a is the first term (i.e 5 )

n is the no of term which is to be find (i.e

15)

d is common difference ( i.e 5)

therefore Tn= 5+(15-1)5

= 5+(14*5)

=5+70

Tn=75