Question

Find the proportion of the data that must lie in (M-8σ, M+8σ) when M=7.013 and σ=3.125.

Answer 1

Assuming a normal distribution, approximately 99.7% of the distribution already falls within 3 standard deviations of the mean. You're asking about how much of it falls within 8 standard deviations of the mean, which may as well be 100%.

If you're asking for more precision, it's roughly 99.99999999999987%.