Question

Ramkali saved 5 rupees in the first week of a year and then increased her weekly savings byby 1.75 rupees.If in the nth wrek her weekly savings becpme 20.75 rupees.Find n?

Answer 1

Here,
a=5
d=1.75
an=20.75
an=a+(n-1)d
20.75=5+(n-1)1.75
15.75=(n-1)1.75
15.75÷1.75=n-1
1575÷175=n-1
9=n-1
n=10