Answer:
1) $350
2) 55°
3) $300
Step-by-step explanation:
1) The total cost is the cost of the appointment plus the cost of the repair work. The appointment costs $50. The repair work costs $120 per 2 hours. So the total cost is:
C = 50 + (120/2) t
C = 50 + 60t
For 5 hours of work, the cost is:
C = 50 + 60(5)
C = 350
It costs $350.
2) The temperature starts at 70°. It drops 10° in 4 hours. So the temperature after t hours is:
T = 70 + (-10/4) t
T = 70 − 2.5t
After 6 hours:
T = 70 − 2.5(6)
T = 55
The temperature is 55°.
3) Jennie's total pay is her weekly pay plus her commissions. If her commission is x% of her sales, then her pay is:
P = 250 + (x/100) S
When her sales is $1000, her pay is $275.
275 = 250 + (x/100) 1000
275 = 250 + 10x
25 = 10x
x = 2.5
So her pay is:
P = 250 + (2.5/100) S
When S = $2000:
P = 250 + (2.5/100) 2000
P = 250 + 50
P = 300
Her total pay is $300.
The answer is the first one.
Knowing that population density is like a rate, people per a given area, you would take the amount of people and divide by the area.
3.11E7/7.69E6 = 4.02 people per km squared.
Also the “E” is another way to write times 10 to a power and I recommend using that notation when plugging it into a calculator.
Answer:
An airplane cruises 1 kilometer in 1/12 of a minute. What is its cruising speed?<u>200</u>
Answer:
Yes
Step-by-step explanation:
First, suppose that nothing has changed, and possibility p is still 0.56. It's our null hypothesis. Now, we've got Bernoulli distribution, but 30 is big enough to consider Gaussian distribution instead.
It has mean μ= np = 30×0.56=16.8
standard deviation s = √npq
sqrt(30×0.56×(1-0.56)) = 2.71
So 21 is (21-16.8)/2.71 = 1.5494 standard deviations above the mean. So the level increased with a ˜ 0.005 level of significance, and there is sufficient evidence.
Answer:
blue green and yellow
Step-by-step explanation:
