Question

A boy saves 1P to-day, 2P tomorrow, 3P day after tomorrow. How much he can save in 12 days?

Answer 1

Answer:

78

Step-by-step explanation:

1 + 2+ 3 + ...........................+ up to 12 days.

a = 1, d = 1

Sn = n[2a+(n-1)d] 2

(a)

= 6[2+(11)] =(13)6 = 78

I hope this helps! :D

Answer 2

Answer

78

Step-by-step explanation:

given 1+2+3+- - - +12 days

a=1 , d=a2-a1=2-1=1

s(n)=n(2a+(n-1)d)

     = 6(2+12-1)

     = 6(13)

     = 78

   

HOPE IT IS HELPFULL