Answer:
Robert
Step-by-step explanation:
If Robert runs 3 miles in 45 minutes, by the end of 90minutes, Robert would have covered 6miles, while Jacob covered 5miles in 90 minutes, therefore, Robert ran faster than Jacob.
40 and 21 do not have common factors, except for one. So the answer is 1.
Answer:
18 kmh
Step-by-step explanation:
Given: Speed of cyclist is 9 km/h more than skater´s speed.
Distance covered at the given time by cyclist is 45 km and by skater is 30 km.
Let´s assume the speed of skater be "x"
∴ Speed of cyclist will be 
Remember; time= 
We know the time taken by both cyclist and skater are same.
∴ we can form an equation to find the speed of skater.
Time taken by cyclist= time taken by skater
⇒ 
Multiplying both side by 
⇒ 
Using distributive property of multiplication
⇒
Subtracting both side by 30x
⇒
Dividing both side by 15
⇒
∴
Hence, speed of the skater is 18 kmh
Here is the equation for this word phrase:
1 + 2 = 9 / 3
Quotient is the result of division.
Answer:
E(M) = 23/3
Var(M) = 53/9.
Step-by-step explanation:
There are three possible values for M: 4, 6, and 10.
.
That's six unique combinations in total. If the balls are drawn randomly, the probability for getting each combination shall be equal. That is:
.
Consider the formula for the expected value of a discrete random variable:
.
Formula for the variance of a discrete random variable (note that this formula can take many other forms):
.