# 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:

$p_1 = 100 \cdot \dfrac{ 14}{ 6+14+15} = 40 \%$
$p_2 = 100 \cdot \dfrac{ 6 + 14}{ 6+14+15} = 57.1 \%$

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