Question

the 7th term of series1,-1/2,1/4

Answer 1

a=1d=-1/2

a7=a-6d

a7=1+3

4

Answer 2

Answer:

The given series is a GP series.

GP is a series which has a common ratio between it's consecutive terms.

GP = 1, -0.5, -0.25, ...

Here, the first term ( a ) = 1 and the common ratio ( r ) = -0.5

We know that general formula of any term in GP is arⁿ⁻¹

Here, 'n' represents the cardinal value of the term.

According to the question, we are asked to find the 7th term. Hence n = 7.

Substituting in the expression we get,

⇒ ( 1 ) ( -0.5 )⁷⁻¹

⇒ ( -0.5 )⁶

⇒ 0.015625

The negative sign is not present due to even power ( 6 ).

Hence the 7th term of the given GP series is 0.015625.