VCAA 2003 quick prob question

[D.H]

For Q1b) I got d=0.2
but the VCAA assessment report says d=1.7

Am I missing something?

[sin0001]

It's considered size fault if it's NOT within d cm from either side of the mean. Question asks find d cm, if size fault is 0.15, that means the center prob. must 0.85. So using inv. norm. (Center = 0.85), you get 138.27, which makes d, 1.73