Question

How many terms of the AP 78, 71, 64 ... are needed to give the sum 468? Also find the last term of this AP.

​

Answer 1

Answer:

a=78

d= -7

an= 468

an = a+(n-1)d

468 = 78+(n-1)(-7)

468= 78+ (-7n) +7

468-85 = 7n

$(468 - 85) \div 7 = n$

383/7 = n

n=55

PLEASE MARK AS BRAINALIST

Answer 2

Answer:

SEE THE ATTACHMENT ABOVE ⬆️⬆️⬆️⬆️⬆️⬆️

_________________________________

FOLLOW ME ❤❤❤❤‼‼

_________________________________