Suppose a regional computer center wants to evaluate the performance of its disk memory system.One measure of performance is the
average time between failures of its disk drive. To estimate this value, the center recorded the time between failures for a random sample of 45 disk-drive failures. The following sample statistics were computed: s . 215 hours # 1,762 hours Estimate the true mean time between failures with a 90% confidence interval. a) ) If the disk memory system is running properly, the true mean time between failures will exceed 1,700 hours. Based on the interval, in part a, what can you infer about the disk memory system?
1 answer:
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Answer:
Ratio states that it shows the relative sizes of two or more values.
i,e a to b or a: b or
(1)
Given the statement: A zoo has 17 monkeys and 12 chimpanzees
Write this situation in three ways, comparing the first quantity to the second quantity.
By definition of ratio:
Ratio in three ways are:
17 to 12
17 : 12
or we can write this as 17 over 12.
therefore, Option B is correct.
(2)
As per the statement: In Largo City, about one in every nine homes contains four televisions
Write this situation in three ways in the form of ratio, comparing the first quantity to the second quantity.
By definition of ratio:
Ratio in three ways are:
4 to 9
4 : 9
therefore, only options C is correct.
(3)
write three ratios for 7 over 35
By definition of ratio;
We have;
Divide both numerator and denominator by 7 we have;
.....[A]
⇒
Multiply both numerator and denominator by 2 in A we get;
Similarly,
Multiply both numerator and denominator by 3 in A, we get
Therefore, 3 ratios equal to 7 over 35 are;
or we can write it as one-fifth
or two -tenths
or three over fifteen
hence, Option D is correct.
(4)
Given the statement: Jake sold 28 tickets to the school fair, and Jeanne sold 21 tickets
Number of ticket Jake sold = 28 ticket.
Number of ticket Jeanne sold = 21 ticket.
To find: Number of ticket Jeanne sold to number of ticket Jake sold.
By definition of ratio
⇒
Therefore, the ratio in simplest form is,
