Answer:
Speed = 20 mi/h
Explanation:
There are two points A and B
Distance between both the points are define with function -20t + 45 miles
where t represent the number of hours of travelling.
Now firstly we find the initial position. At starting time is 0, so we put t=0 in given function of t.
At t=0;
d₀ = -20(0) + 45 = 0 + 45 = 45 miles
Now we find the distance travell after starting first hour.
Than we put t = 1 in the given function
At t = 1;
d₁ = -20(1) + 45 = -20 + 45 = 25 miles
Difference between d₁ & d₀ is
45 - 25 = 20 miles
We see that in one hour, total distace is covered 20 miles
Now we use time, speed, distance relation
Speed = distance/time
Speed= 
Speed = 20 miles/hour
That's the final answer.
I hope it will help you.
Answer:
you have 33 ones and 40 fives
Step-by-step explanation:
Answer:
The length will be letter C, 50 m
Answer:
D
Step-by-step explanation:
We can test each pair making each ratio into its simplest form.
For A 2/3 is already in its simplest form and 9/15=3/5. they are not equivalent.
For B, 5/8 is already in its simplest form and 15/21=5/7. they are not equivalent.
For C, 3/12=1/4, and 6/18=1/3. They are not equivalent.
For D, 4/10=2/5, and 12/30=2/5. They are equivalent.
Answer:
a) 615
b) 715
c) 344
Step-by-step explanation:
According to the Question,
- Given that, A study conducted by the Center for Population Economics at the University of Chicago studied the birth weights of 732 babies born in New York. The mean weight was 3311 grams with a standard deviation of 860 grams
- Since the distribution is approximately bell-shaped, we can use the normal distribution and calculate the Z scores for each scenario.
Z = (x - mean)/standard deviation
Now,
For x = 4171, Z = (4171 - 3311)/860 = 1
- P(Z < 1) using Z table for areas for the standard normal distribution, you will get 0.8413.
Next, multiply that by the sample size of 732.
- Therefore 732(0.8413) = 615.8316, so approximately 615 will weigh less than 4171
- For part b, use the same method except x is now 1591.
Z = (1581 - 3311)/860 = -2
- P(Z > -2) , using the Z table is 1 - 0.0228 = 0.9772 . Now 732(0.9772) = 715.3104, so approximately 715 will weigh more than 1591.
- For part c, we now need to get two Z scores, one for 3311 and another for 5031.
Z1 = (3311 - 3311)/860 = 0
Z2 = (5031 - 3311)/860= 2
P(0 ≤ Z ≤ 2) = 0.9772 - 0.5000 = 0.4772
approximately 47% fall between 0 and 1 standard deviation, so take 0.47 times 732 ⇒ 732×0.47 = 344.