Answer: 15
Explanation:
The 11th term of arithmetic progression is 43. We can use this to get the common difference which will be:
a + (n - 1)d = 43
where,
a = first term = 3
n = nth term = 11
d = common difference = unknown
Therefore, a + (n - 1)d = 43
3 + (11 - 1)d = 43
3 + 10d = 43
10d = 43 - 3
10d = 40
d = 40/10
d = 4
Common difference = 4
Therefore, 4th term will be:
= a + (n - 1)d
= a + (4-1)d
= a + 3d
= 3 + 3(4)
= 3 + 12
= 15
The 4th term is 15