Memorize the definition of standard deviation: the sd is the square root of the average of the squared deviations of the mean. Wow. Let's do it.
Step 1. First we need the mean. That's easy. Add them up and divide by the count. Check if you get 16.88/5 = 2.81333.
Step 2. Now we're going to subtract this from each of the values, and square the result. Don't worry about negative signs, the squaring will get rid of those. Example for the first number:
(1 - 2.813)^2 = 3.29
The list of numbers I get is (rounded, in reality round as little as possible):
3.29, 2.60, 1.41, 2.35, 1.66, 6.18
Step 3: Add them all up. I get 17.49.
Step 4: Divide by the count of numbers. 17.49/6 = 2.91
Step 5: Take the square root from this result. SQRT(2.91) = 1.707305
TIP: Use excel to do all these steps, then run the set of numbers through Excel's built-in sd function (called STDEV.P) and see that you get the same result!
The answer is 16 because 8 goes into 24 3 times so 8 + 8 is 16
Answer:
Step-by-step explanation
Use Pythagoras theorem. The distance between the cars, 8km, is the hypotenuse of a right angled triangle, one leg of which is 6km and the other of which is, say, x km
x = sqrt(8^2 - 6^2) km.
You can crunch the numbers.
Answer:
x - 5
Step-by-step explanation:
x^2 - 3x - 10
= (x + 2)(x - 5)
Sine the width is (x + 2), the length is (x - 5).
Hope this helped!
Combine like terms
-7y² + 6y² - 2y² = -3y²
4y + (-5y) - (-9y) = 4y - 5y + 9y = 8y
9 + 9 - (-2) = 9 + 9 + 2 = 20
-3y² + 8y + 20 is your answer
hope this helps
