Given a mean of 571 and a standard deviation of 236.5 what is the z-score of the value 724 rounded to the nearest tenth

Z- score is a statistical tool that is used to determine the probability of finding a number or a value under a normal distribution plot. A normal distribution assumes that the mean is equal to zero and that the standard deviation is equal to 1. Using the z-score table, we can find the probability either on the right side or the left side. The expression to find the z score is z = (x -∪)/∅ where ∪ is the mean and ∅ is the standard deviation. Given ∪ equal to 571, ∅ equal to 236.5 and x equal to 724, we substitute these values to 
z = (x -∪)/∅ 
z = (724-571)/236.5
z =  0.6469

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