Answer: 413343
Explanation:
This is a geometric progression. First and foremost, we've to find the common ratio which will be:
= 2nd term / 1st term
= -21/7
= -3
The formula to find the 11th term will be:
= ar^n-1
where,
a = first term = 7
r = common ratio = -3
n = number of terms = 11
Therefore, ar^n-1 = 7 × -3^11-1
= 7 × -3^10
= 7 × 59,049
= 413343
Therefore, the 11th term of the sequence is 413343.