Let the three numbers be x, y and z respectively, then
x + y + z = 62 . . . (1)
y = x - 4 . . . (2)
z = 4x . . . (3)
The above three expressions could be used to represent the numbers.
Solving the three equations, putting (2) and (3) into (1) gives
x + x - 4 + 4x = 62
6x - 4 = 62
6x = 62 + 4 = 66
x = 66/6 = 11
x = 11.
y = 11 - 4 = 7
z = 4(11) = 44
x = 11, y = 7, z = 44.
Answer:
d = 3.5t + 1
Step-by-step explanation:
The linear function would have to multiply the speed she runs at the track by the number of hours that she spent running. Then it should add this amount to the 1 mile that she walked to get to the track. If we use the variable d as the total distance that she ran and walked, and the variable t to represent time then we would create the following linear function/model.
d = 3.5t + 1
The line of reflection is what the graph flips over. You can find the line with two points, and a point on the reflection line is the midpoint of a point and the corresponding point in the after-image.
The first one reflects over the y-axis, or x=0. One point is (-2, 1) and its corresponding point is (2, -1). The midpoint is found by the average of the two coordinates, which is (0,0). Pick another pair of points and find the midpoint which you should get (x,0).
You have two points (0,0) and (x,0) and they form a line, which is the y-axis, or x=0.
The line of reflection for the 1st one is x=0 (y-axis).
Answer:
95%.
Step-by-step explanation:
We have been given that the lifetimes of light bulbs of a particular type are normally distributed with a mean of 370 hours and a standard deviation of 7 hours.
We are asked to find the percentage of the bulbs whose lifetimes lie within 2 standard deviations to either side of the mean using empirical rule.
The empirical rule (68-95-99.7) states that approximately 68% of data points lie within 1 standard deviation of mean and 95% of data points lie within two standard deviation of mean. 99.7% of data points lie within three standard deviation of mean.
Therefore, approximately 95% of data points lie within two standard deviation of mean.
Answer:
$763
Step-by-step explanation:
