Write the first three terms of the geometric sequence that has a1= 120 and whose common ratio is r = -1/2

For geometric sequence, you multiply the common ratio to the previous one.

120 × (-1/2) = -60

-60 × (-1/2) = 30

30 × (-1/2) = -15

So your first three terms is

-60 , 30 , -15

Hope this helped! Brainliest is always welcome :)

step-by-step explanation:

you divide the denominator by the numerator on both sides and if the quotients are equal then the fractions are equivalent

1/800 is the right answer