Answer: 0.82 miles per gallon
Step-by-step explanation:
Given : Jenna has bought a new hybrid car. Each week for a period of seven weeks, she has noted the fuel efficiency (x) (in miles per gallon) of her car.
The results are :45 44 43 44 45 44 43
The formula to find the standard deviation is given by :-
First we find mean of the given data ,
Now,
Now, standard deviation of the above results will be :-
Hence, the standard deviation of these results = 0.82 miles per gallon
Answer:
The area of ∆DEF = 4.5in²
Step-by-step explanation:
From the above diagram,
∆BAC ~∆DEF
It is important to note that if two triangles are similar, the ratio of their areas is equal or equivalent to the ratio of the areas of their sides
This means for the above question, that
We have the bigger triangle = ∆BAC has a side of 4 in and Area = 8 in²
The small triangle has a side of 3in
Finding the scale factor k = ratio of the sides of both Triangles
k = 4/3
k² = (4/3)²
k² = 16/9
Hence,
Area of ∆BAC/ Area of ∆DEF = 16/9
8in²/Area of ∆DEF = 16/9
We cross Multiply
8 in² × 9 = Area of ∆DEF × 16
Divide both sides by 16
Area of ∆DEF = 72/16
= 4.5in²
Therefore, the Area of ∆DEF rounded to the nearest tenth = 4.5in²
A rectangle is plotted on the coordinate grid. It has vertices at (-3, 5), (4, 5), (4, -1), and (-3, -1). Which choices below are the dimensions of the rectangle?
Answer
(-3,5)
We know that
The Euler's formula state that, the number of vertices, minus the number of edges, plus the number of faces, is equal to two
V - E + F = 2
clear F
F=2-V+E
in this problem
V=8
E=14
F=?
so
F=2-8+14
F=8
the answer is8 faces
