Question

if m times the mth term of an ap is equal to n times the nth term, find the 16th term
​

Answer 1

Step-by-step explanation:

The given sequence is 20, 17, 14, ..............

The nth term of this sequence is given by t

n

=a+(n−1)d.

To find the first negative term, t

n

should be less than 0.

We have 'a' = 20, 'd' = -3

a+(n−1)d<0

⟹20+(n−1)(−3)<0

⟹20+3−3n<0

⟹23−3n<0

⟹3n>23orn>

3

23

.

The next natural number greater than 7.6 is 8.

Hence, the 8th term is the first negative number.