Remember Standard deviation and percentages
We have found
68% = 1 SD
95% = 2 SD
99.7% = 3 SD
So these are:
68%, 95%, 99.7%
Or
68, 95, 99.7
To remember this ratio see the following:
Jay Z was sick and late (68%) which got him fired from his nine to five (95%) job, giving him 99 problems but 7up (99.7%) wasn’t one.
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