Answer:
12.5 s
Step-by-step explanation:
If acceleration is constant, speed is proportional to time. To increase the speed by 50 km/h, the car will need an additional time given by ...
t/(50 km/h) = (20 s)/(80 km/h)
t = (20 s)(50/80) . . . . . multiply by 50 km/h
t = 12.5 s
It will take 12.5 more seconds for it to reach a speed of 130 km/h.
Answer:
The 98% confidence interval of the proportion = (0.312, 0.374)
Step-by-step explanation:
(Give answers accurate to 3 decimal places.)
The formula for Confidence Interval of Proportion is given as:
p ± z × √p(1 - p)/n
Where p = Proportion = x/n
x = 440
n = 1282
p = 440/1282 = 0.34321372854
Approximately = 0.343
z = z-score of 98 % confidence interval
= 2.326
Confidence Interval =
= 0.343 ± 2.326 × √0.343(1 - 0.343)/1282
= 0.343 ± 2.326 × √0.225351/1282
= 0.343 ± 2.326 × √0.00017578081
= 0.343 ± 2.326 × 0.01325823555
= 0.343 ± 0.03083865589
0.343 - 0.03083865589
= 0.31216134411
Approximately = 0.312
0.343 + 0.03083865589
= 0.37383865589
Approximately to = 0.374
Therefore, the 98% confidence interval of the proportion = (0.312, 0.374)
Answer:
305 miles per hour
Step-by-step explanation:
61 miles per hour
61(5)= 305 miles/ hour
Answer:
(-4,9)
Step-by-step explanation:
To solve the system of equations, you want to be able to cancel out one of the variables. In this case, it'd be easiest to cancel out the x variables. To do this, you'll want to multiply everything in the first equation by 2 (2(x-5y=-49)=2x-10y=-98). Then, you can add the two equations together. 2x and -2x will cancel out, so you'll be left with -11y=-99. Next, solve for x by dividing both sides of the equation by -11, which will give you y=9. This is your y-coordinate! At this point, you're halfway to the answer as you just need your x-coordinate. It's not too difficult to find the x-coordinate, since you just substitute 9 into one of the equations. It doesn't matter which one you choose as you should get the same answer with both. I usually substitute the y-value into both equations, though, just to make sure I'm correct. Once you put the y-value into the equations, you should get x=-4 after solving it. :)
Answer:
9.8 lbs
Step-by-step explanation:
4 1/3 + 5 5/6= 10 1/6
20 - 10 1/6 = 9.8
