Question

Neela saves in Mainland Bachat Gat ₹5 on first day ₹7 on second and ₹9 on Third day What will be her saving in month of August

Answer 1

first day saves = 5
second day saves = 5+2 = 7
third day saves = 7+2 = 9 and so on..
common difference = 2
In august month has 31 days
therefore , no. of days 31
now,
total saving = 31/2 (2*5 + (31 - 1) 2 )
= 31(5 + (31 - 1)
= 31( 35)
= 31 × 35
= 1085

Answer 2

Let her pocket money be Rs.

. Now, she takes Rs. 1 on day 1, Rs. 2 on day 3 and so on till the end of the month, from this money. <br> i.e.,

which form an AP in which terms are 31 and first term (a) = 1, common difference (d)

Sum of first 31 terms

Sum of n terms,

So, Kanika takes Rs. 496 till the end of the month from this money. Also, she spent Rs. 204 of her pocket money and found that at the end of the month she still has Rs. 100 with her. Now, according to the condition,

Hence, Rs. 800 was her pocket