Question

. In an Arithmetic progression the sum of first four terms is 20 and the sum of first three terms is 12 then find the fourth term of the arithmetic progression.​

Answer 1

Answer:

4th term in A.P a+3d=10

Step-by-step explanation:

sum of first 3terms take a-d,a,a+d

so sum a-d+a+a+d=12

3a=12

a=4

first 4terms a-d,a,a+d,a+2d,

sum. a-d+a+a+d+a+2d=20

4a+2d=20,here a=4 so

4(4)+2d=20

16+2d=20

2d=20-16

2d=4

d=4/2=2

then 4th term in ap a+3d=10

Answer 2

Answer:
If the sum of first four terms and the sum of first three terms of an AP is 20 and 12 respectively, then the fourth term is 8

Step-by-step explanation:

Given

Sum of first four terms of the AP = 20

Sum of first three term of the AP = 12

Then, the fourth term is :


Sum of first four terms - sum of first three terms = 20-12 = 8

So the fourth term is 8