1. Chebyshev's Theorem

The mean amount spent by all customers at an organic food market is estimated to be $48, and the standard deviation is estimated to be$12. According to Chebyshev's Theorem, at least what percentage of customers would be expected to spend between $27 and$69? Express your answer to two decimal places and show step by step work

im lost

2. Re: Chebyshev's Theorem

What does Chebyshev's theorem say?

(Is the standard deviation 12 or 21?)