Answer:
the mistake is that to "remove" the 1/2 on the left you would have to multiply by 2 (or divide by 1/2 but no one does that)
the result would be that 2h-4 = 10 should actually be 2h-4 = 20
Step-by-step explanation:
Answer:
28.6, that is, about 29 are expected to be defective
Step-by-step explanation:
For each battery, there are only two possible outcomes. Either it is defective, or it is not. The probability of a battery being defective is independent of other betteries. So the binomial probability distribution is used to solve this question.
Binomial probability distribution
Probability of exactly x sucesses on n repeated trials, with p probability.
The expected value of the binomial distribution is:

The probability that a battery is defective is 1/14.
This means that 
400 batteries.
This means that 
How many are expected to be defective?

28.6, that is, about 29 are expected to be defective
Answer:
we dont have all the information and dont know the question
There are 8 students in each class and there are 5 classes
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