Answer: Hello There!................
Mean = Sum of observation / total number of observation
Mean = 1.35m
1.35 = Sum of length of 7 wood planks/ 7
1.35*7 = Sum of the length of 7 wood planks
9.45 = Sum of the length of 7 wood planks
Let the length of extra added wood plank = x
So,
(Sum of the length of 7 wood planks + x) / 8 = 1.4m
(9.45 + x) / 8 = 1.4
9.45 + x = 1.4 * 8
9.45 + x = 11.2
x = 11.2- 9.45
= 1.75
So,
The length of extra added wood plank = 1.75m
Step-by-step explanation:
Mark me brainest please. Hope this helps. Anna ♥
Answer:
I did my best, but it has been a while. I really hope that this helps
Step-by-step explanation:
so you can find the perimeter of a circle
-----The perimeter of a circle is π × d where d is the diameter so half of that is 1/2 π × d. But If you are going to walk around a semicircle, you need to go halfway around the circle and then across a diagonal to get back to where you started, so the perimeter is 1/2 π × d + d.
78....................................................
Answer:
1.5
Step-by-step explanation:
The given expression for the area, 81x² - 4y², is a difference of two squares. The first term is the square of 9x and the second term is the square of 2y. The factors of this difference and the therefore the dimensions of the rectangle are, 9x - 2y and 9x + 2y.