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Seabass592
Mar 20, 2007, 01:20 PM
The fountain contains 20 pennies and 9 dimes. A coin is randomly taken and not replaced. A second coin is randomly taken. What is probability that both coins are pennies?


-and-


Two dice are rolled. What is the probability that the sum of the numbers rolled is:

(a) 8? (b) a number less than 8?

:) :) :) :) :)

Capuchin
Mar 20, 2007, 01:33 PM
What's the probability of the first coin being a penny? What's the probability of the second coin being a penny? Therefore what's the probability them both being pennies?

Your second question is probably more easily worked out if you write out all the combinations of 2 dice being rolled, and their totals, you can use this to count up the probabilities you need.

If you need more help, please do ask, I prefer to help you rather than give the answer :)