28 x 2 = 56 half dollar coins
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.
Answer:
B. 28 minutes
Step-by-step explanation:
According to the given statement,
William weeds the whole garden in 45 minutes, then in one minute he will weed 1/45 of the garden
and
similarly, 1/75 of the garden in one minute.
When they both will work together, they will weed (1/45+1/75) of the garden in one minute
Solving the equation:
= 
Garden weeded in one minute by both = 0.036
So, number of minutes to weed whole garden = 1/0.036
= 27.77 minutes
Rounding off will give us: 28 minutes
So,
Option B is the correct answer ..
Sum of all adjacent angles is 180°.
3x + 12 + x = 180
4x + 12 = 180
4x = 168
x = 42°
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Answer: x = 42°
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81.49 is the answer. Have a great day!
