Answer:
Mean age: 48
Standard deviation: 4
Step-by-step explanation:
a) Mean
The formula for Mean = Sum of terms/ Number of terms
Number of terms
= 42 + 54 + 50 + 54 + 50 + 42 + 46 + 46 + 48+ 48/ 10
= 480/10
= 48
The mean age is 48
b) Standard deviation
The formula for Standard deviation =
√(x - Mean)²/n
Where n = number of terms
Standard deviation =
√[(42 - 48)² + (54 - 48)² + (50 - 48)² +(54 - 48)² + (50 - 48)² +(42 - 48)² + (46 - 48)² + (46 - 48)² + (48 - 48)² + (48 - 48)² / 10]
= √-6² + 6² + 2² + 6² + 2² + -6² + -2² + -2² + 0² + 0²/10
=√36 + 36 + 4 + 36 + 4 + 36 + 4 + 4 + 0 + 0/ 10
=√160/10
= √16
= 4
The standard deviation of the ages is 4
So, angles A and B added together is 130° which makes the whole angle = 180°-130°=50°
The answer is 180° because it is a supplementary angle and all supplementary angles equal 180° so, all the angles added makes 180°
Answer:
-33/10 or -3.3
Step-by-step explanation:
-3x = 4y is the answer
Because:
-3 (-4) = 4 (-3)
-7 = -12
3. well you know to get the perimeter of a rectangle, you add together 2L and 2W. A way you could write this is-- 2x + 2(x+5). You would just need to simplify it--2x + 2x+10 --4x+10.
4. To find out how much they have in all, you just need to add them together--x+24.50 + 7x-52.34. Now you need to simplify the problem by putting the values together. x+7x + 24.50-52.34-- you can do that.
5. To do this one, look back at 3. and just change the numbers. Drawing a picture may help. The sides are x+y and the top and bottom are 5y+12.
6. same as 5.
7. I think this one is just solving for x first. make Tom and his brother's equations equal to zero and get x by itself. Tom's equation would be 8x-30=0 ----His brother's would be 5x+10. You need to find out what x equals then plug it back into the equations. To plug it in, have x's value take x's place then find the number of candies they have.
8. The easiest way to start is by writing the same values together. 4x+3x-5x-5-7+2---then just add the x's together and add the numbers together.
9. Multiply the outer numbers to both of the values in the parentheses. 2(x-4) would turn out to 2x-8. then do the same as 8. and put the same values together to simplify.
10. get x by itself. Start by multiplying 3 by x and 4 in the parentheses. simplify the numbers then subtract it from both sides to get x alone.