Answer:
-0.924
Step-by-step explanation:
The magnitude of the correlation coefficient is the square root of the variation.
|r| = √0.854
|r| = 0.924
The sign of the correlation coefficient is the same as the slope of the line of best fit. In this case, it's negative.
r = -0.924
Answer:
m = E/c²
Step-by-step explanation:
E = mc²
mc² = E
Divide both sides by c².
m = E/c²
Time taken to reach a person located 5m from the source is 0.2s
<u>Explanation:</u>
Given:
Frequency, f = 10Hz
Wavelength, λ = 2.5m
Distance, d = 5m
Time, t = ?
We know:
velocity = f X λ
v = 10 X 2.5
v = 25 m/s
We know:
Distance = speed X time
On substituting the value we get:
5 = 25 X t
t = 0.2 seconds
Therefore, time taken to reach a person located 5m from the source is 0.2s
<span>let x = the original no. of students
then
(x+10) = the actual no. that went on the trip
:
= the original cost per student
and
= the actual cost
:
Original cost - actual cost = $12.50
- = 12.50
multiply equation by x(x+10)
x(x+10)* - x(x+10)* = 12.50x(x+10)
Cancel the denominators
1500(x+10) - 1500x = 12.5x(x+10)
1500x + 15000 - 1500x = 12.5x^2 + 125x
Combine on the right to form a quadratic equation
0 = 12.5x^2 + 125x - 15000
Simplify, divide equation by 12.5
x^2 + 10x - 1200 = 0
You can use the quadratic formula; a=1; b=10; c=-1200, but this will factor to
(x + 40(x - 30) = 0
The positive solution is what we want here
x = 30 students in the original group
Check this by finding the cost per student for each scenario
1500/30 = $50.00; original cost
1500/40 = $37.50; actual cost
---------------------
saving: $12.50</span>
