Question

Find the 20th term from the last term of the ap is 3,8,13,....253.

Answer 1

Answer

158

Step-by-step explanation:

Here a=3,

d= 8-3=5

First lets find out the term of 253.

a+(n-1)d=253

3+(n-1)5=253

3+5n-5=253

Therefore n=51

20th term from the last term= (51-19)th term

Therefore, 32nd term

T32 = 3+(32-1)5=

158

Hope this helps you

Answer 2

Given

a= 3, d= 8-3= 5 Tn = 253

  Tn= a+(n-1)d

=> 253=3+(n-1)5

=> 253=3+5n-5

=> 253-8=5n

=> 245=5n

=> n=49

no. of terms = 49

l=a-(n-1)d

=> 3-(20-1)5

=> 3-19 x 5

=> 3-95

=> l=92

HOPE THIS HELPS YOU A LOT