How to calculate probability of value being between two numbers using Chebyshev's inequality?

I can't figure out how to calculate P(4 < X < 12) using Chebyshev's. It's given that mean = 7.9 and variance = 7.9

• are you sure the mean is 7.9 and not 8? – tommik Oct 17 at 21:30
• the theoretical mean is 8 but the empirical mean is 7.9 so I guess you're right about that – yeetbro Oct 17 at 21:31
• Sounds like there are some relevant details in the problem that you haven't told us about... – Ian Oct 17 at 21:39

$$\mathbb{P}\{|X-\mu|<\epsilon\}\geq 1-\frac{\sigma^2}{\epsilon^2}$$
$$\mathbb{P}\{|X-8|<4\}\geq 1-\frac{7.9}{4^2}=0.50625$$