Work out the z scores for 51 and 54
z1 = (51 - 57.5) / 6.5 = -1
z2 = (64 - 57.5)/6.5 = 1
from tables of normal distribution this value os 3413 + 3413 = 68.26%
so the answer is c
You should try C I’m not sure but try I guess!
2s+14=12
2s=-14+12
2s=-2
s=-2÷2
s=-1
