Answer:
i am pretty sure 90
Step-by-step explanation:
<h3>
Answer: </h3><h3>
speed of train A = 44 mph</h3>
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Work Shown:
x = speed of train A
y = speed of train B
"train A travels 4/5 the speed of train B" (I'm assuming "train one" is supposed to read "train B"). So this means x = (4/5)y
distance = rate*time
d = x*7
d = (4/5)y*7 = (28/5)y represents the distance train A travels
d = y*7 = 7y represents the distance train B travels
summing those distances will give us 693
(28/5)y + 7y = 693
5*( (28/5)y + 7y ) = 5*693
28y + 35y = 3465
63y = 3465
y = 3465/63
y = 55
Train B's speed is 55 mph
4/5 of that is (4/5)y = (4/5)*55 = 4*11 = 44 mph
Train A's speed is 44 mph
Answer:
<h2>The circumference is multipled by 4.</h2>
Step-by-step explanation:
The formula of an area of a circle"

The formula of a circumference of a circle:

The area multipled by 16:

The radius has increased fourfold, therefore:

The circumference is multipled by 4.
You can calculate the area and check the circumference:

Calculate the radius:
<em>divide both sides by π</em>

Calculate the circumference of both circles:



Answer:
Test statistic,
(to 3 dp)
Step-by-step explanation:
Deviation, d = x -y
Sample mean for the deviation


Standard deviation: 


SD =2.93
Under the null hypothesis, the formula for the test statistics will be given by:


Answer:
2n(8n + 5)
Step-by-step explanation:
you need to see what you can take out of both the numbers.
ex they both have an 'n' and they both are divisible by 2