Bulbs

In the box are 6 bulbs with power 75 W, 14 bulbs with power 40 W and 15 with 60 W. Calculate probability that a randomly selected bulb is:

Result

40 W:  40 %
75 W or 40 W:  57.1 %

Solution:

Solution in text 40 W:=
Solution in text 75 W or 40 W:=

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To solve this example are needed these knowledge from mathematics:

Would you like to compute count of combinations?

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