<h3>
Answer: 50</h3>
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Explanation:
We simply multiply the two values given to us
600*(1/12) = 600/12 = 50
We expect about 50 bulbs to be defective.
Note how if we had 50 bad bulbs, then 50/600 = (1*50)/(12*50) = 1/12 of the batch of 600 bulbs is defective.
For it to double its price the price has to be +100% more, and every year you get +2.4%, so you do:
100/2.4≈ 42 years or 41.66666667.. years.
Depends on where you are in the math book but this would be the most simple way.
n= number
sqar(-1) = i

That's 7.68% = 7.7% (rounded)
Note: C(5, 4) is the number of combinations of 5 things taken 4 at a time. You may have seen this written as

In general,