Answer: I really don't know yet.
Step-by-step explanation:
Another day. 
The answer I believe is -2. Thank you come again
ANSWER
1 bell shape
2 to find probability when sampling
EXPLANATION
1 In a normal distribution, the mode,mean and median are equal.
As a result, the distribution is neither skewed to the right or left.
The shape of the normal distribution looks like a bell.
That is why it is also called the bell curve.
2. The area under the normal curve is 1.
The line of symmetry of the bell shaped distribution divides it into two halves with area 0.5 each.
The normal curve is therefore used to find the probabilities of a sample distributions.
The keyword is "sum" which tells you x, y, and z are being added. One half of the sum means that the sum of the three numbers is going to be divided by 2.
x + y + z
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2
1. Multiply each equation so they end up with the same coefficient
2. Subtract your second equation from the first
3. Solve for one of the variables (I tend to solve an equation that only contains 2 variables if possible. So it would be if you have one question with x and y, solve for the easier one)
4. Substitute the variable you found in the least step into one of the other equations and find a second variable.
5. Substitute both variables you found into the last equation and there you should be left with x, y, and z :))
I hope this helped sksjsk if it didn’t I could write it out to hopefully help more :)
