K2R7 is correct in his response. The author stated that the draw was without replacement. Therefore, drawing 2 red balls would be (4/6)*(3/5) = .400. Drawing 2 blue balls would be (2/6) * (1/5) = .067. Add the two together equals .400 + .067 = .467. Explanation: Without replacement the number of balls (the denominator) would decrease by 1 for each subsequent draw. The first draw would have 6 balls to choose from, the second would have 5, since the ball originally chosen was 'not replaced'.

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I hold 5 college degrees including a BBA in Finance, MBA, DBA, and post-doc in Applied Statistics. I work for a non-profit in Orlando, FL as a business analyst.

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Adrian J. Mayer

I hold 5 college degrees including a BBA in Finance, MBA, DBA, and post-doc in Applied Statistics. I work for a non-profit in Orlando, FL as a business analyst.