Question

Mukta had rs 42.on 4th Jan .2018, she saved rs15. After this day, every day she saved 12 more rupees than the earlier day. Then including the savings, how much total amount did she have up to 30th Jan

Answer 1

so, on the end of 4rth of January, she had ₹57.

Therefore, number of days from 5th to 30th January is 26.

WKT, Sum of n terms of an A.P. = a + (n - 1)d

Where a is the initial amount, n is the no. of days and d is the amount of rupees saved each day.

Therefore the total savings on 30th of Jan would be
$= (57 + (26 - 1)12) \\ = 57 + (25 \times 12) \\ = 57 + 300 \\ =357$

therefore, the total savings at the end of 30th of Jan (including itself) is ₹357