Statistics Problem

[Choudhry347]

I am having a problem solving the Q.3 (ii) of Statistics O level '4040/12/O/N/16'. Can anyone Provide me with the solution.

https://papers.xtremepape.rs/CAIE/O%20Level/Statistics%20(4040)/4040_w16_qp_12.pdf

 

[PlanetMaster]

I am having a problem solving the Q.3 (ii) of Statistics O level '4040/12/O/N/16'. Can anyone Provide me with the solution.

https://papers.xtremepape.rs/CAIE/O%20Level/Statistics%20(4040)/4040_w16_qp_12.pdf

Since the atmospheric pressure is usually about 80mb lower, all measurements are 80mb lower on average and therefore the mean is 80mb lower.
So mean = 1002 - 80 = 922 [1002 is from answer in (i)]

Lowering the mean doesn't affect the range as we are effectively reducing all values by 80, so
Range = Highest measurement - Lowest measurement
= 1012 - 993
= 19

P.S. If this is still unclear, please let me know and I'll be happy to explain further with example.