Geometric mean of 10 observations is 8. If geometric mean of first six observations is 4, then geometric mean of last four observations is

We are given, here geometric mean of 10 observations is 8 and geometric mean of first six observations is 4, then we have to find the geometric mean of last four observations. Let G be the GM of last four observations. ∴ By using grouped geometric mean, i.e., 810=46×G4⇒G4=81046=230212=218⇒G=218/4=242=162