The Brainliest Answer!
The next number is getting divided by 2 in this series

sso the next number will be 1/8 then 1/16 and so on
1 5 1
The last number in the series is 1/4 and what is happening in the series the denominator is being multiplied by 2 so the answer will be 1/8 and the next will be if we multiply 2 in 8 the answer will be 1/16 hence the series is continuing in this way .