5. Write an expression to represent "Six more than the difference of a number and three."

I am Lyosha [343]

For question 7, if we add all votes for tiger and eagle, we get

tiger = 14 + 13 + 8 + 5 = 40
eagle = 6 + 7 + 12 + 15 = 40

so choices A and B are wrong.
C is also wrong because fifth and sixth grade votes for eagle are 6 + 7 = 13 and the 5th and 6th grade votes for tiger are 14 + 13 = 27. clearly 5th + 6th like tiger more.

D is the answer for question 7

question 8

rolling a cube does not affect the other cube so it is all independent probability.
cube: 1 2 3 4 5 6
3 even numbers and 3 odd numbers

so probability of rolling an even number is

1/6 + 1/6 + 1/6 = 3/6 = 1/2

multiplying by total number of rolls, she will get even numberss

300 * 1/2 = 150

about 150 time.
so half of the time, Cassie will roll and even number about half the number of rolls. never exactly since this is all probability. more likely for it to be around 150 times than exactly 150 time.

choice C is answer for question 8

4 0

3 years ago

5) Two machines M1, M2 are used to manufacture resistors with a design

Basile [38]

Answer:

Since M1 has the higher probability of being in the desired range, we choose M1.

Step-by-step explanation:

Problems of normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.

Two machines M1, M2 are used to manufacture resistors with a design specification of 1000 ohm with 10% tolerance.

So we need the machines to be within 1000 - 0.1*1000 = 900 ohms and 1000 + 0.1*1000 = 1100 ohms.

For each machine, we need to find the probabilty of the machine being in this range. We choose the one with the higher probability.

M1:

Resistors of M1 are found to follow normal distribution with mean 1050 ohm and standard deviation of 100 ohm. This means that $\mu = 1050, \sigma = 100$