hello
to solve this question, we need to use a standard normal table (z)
out z-value give = -1.27
this is equivalent to 0.4032
note, i approximated 1.27 to 1.3 and the z-value for -1.3 = 0.4032
to compensated tp the other side of the graph, we should add 0.5 to 0.4032
the area under z = -1.27 is equal to 0.9032 square units or 90.32%