Adding integers with different signs is just like adding or subtracting. First you just have to add all negative integers and also add all positive. After that positive intergers will be deducted by the sum of negative integers
Try making a grid like this. Apologies for the terrible drawing and handwriting. It represents all possible results of rolling two dice and summing their values. The blue column and yellow row represent the values of each die, and the green numbers reptesent their sums.
First, you can see that there are 36 possible values. Second, it's easy to see how many results are greater than 9, since they're all in one corner. And last, you can see just how many are even and how many are odd. Remember to reduce your fractions in the end.
Step-by-step explanation:
Given that the graph shows the normal distribution of the length of similar components produced by a company with a mean of 5 centimeters and a standard deviation of 0.02 centimeters.
A component is chosen at random, the probability that the length of this component is between 4.98 centimeters and 5.02
=P(|z|<1) (since 1 std dev on either side of the mean)
=2(0.3418)
=0.6826
=68.26%
The probability that the length of this component is between 5.02 centimeters and 5.04 centimeters is
=P(1<z<2) (since between 1 and 2 std dev from the mean)
=0.475-0.3418
=0.3332
=33.32%
Vary Directly: y = k*x
Vary Inversely: y = k/x
Because x and y vary directly, our equation will look like the first one.
y = k*x
With the inputted values:
-16 = k * 4
Now, to find k, isolate the variable
k = -16/4 = -4
Your final equation will then look like this:
y = -4 * x
Answer:
0.3075 = 30.75% probability that a person will wait for more than 7 minutes.
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

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.
The standard deviation is the square root of the variance.
In this problem, we have that:

Find the probability that a person will wait for more than 7 minutes.
This is 1 subtracted by the pvalue of Z when X = 7. So



has a pvalue of 0.6915
1 - 0.6915 = 0.3075
0.3075 = 30.75% probability that a person will wait for more than 7 minutes.