Explain this 2021 hsc question (1 Viewer)

[Tony Stark]

 

[C2H6O]

View attachment 48785

ok so theres a few things you need to know:
the area under a normal distribution is 1
the curve is symmetrical at z=0, ie the area on both sides is 0.5

and the table basically gives you the area between the middle line (z=0) to z= the top value in the table

what they're asking for is the area to the right side of z=0.3
you can use subtraction to work out this area

 

[Tony Stark]

Thanks! I kept doing 1 - 0.1179 when it should've been 0.5 - 0.1179