Answer:
<u>True</u>
Step-by-step explanation:
3³ x 4
= 3 x 3 x 3 x 4
= 9 x 12
= 108
<u>True</u>
Answer:
57.78 km/hr
Step-by-step explanation:
Total time taken, t = 6 hours
Total distance covered, d = 520 km
Distance by car = 260
Distance by train = 520 - 260 = 260 km
Train speed = x
Car speed = 2x
Average speed speed = 3x /2
Speed = distance / time
1.5x = 520 / 6
9x = 520
x = 520 / 9
x = 57.777
Average speed of train = 57.78 km/hr
Answer:
D. 62˚
Step-by-step explanation:
Step-by-step explanation:
Lines that are tangent to a circle are perpendicular to the radius of the circle.
Lines that are tangent to a circle are congruent
<span>n = 5
The formula for the confidence interval (CI) is
CI = m ± z*d/sqrt(n)
where
CI = confidence interval
m = mean
z = z value in standard normal table for desired confidence
n = number of samples
Since we want a 95% confidence interval, we need to divide that in half to get
95/2 = 47.5
Looking up 0.475 in a standard normal table gives us a z value of 1.96
Since we want the margin of error to be ± 0.0001, we want the expression ± z*d/sqrt(n) to also be ± 0.0001. And to simplify things, we can omit the ± and use the formula
0.0001 = z*d/sqrt(n)
Substitute the value z that we looked up, and get
0.0001 = 1.96*d/sqrt(n)
Substitute the standard deviation that we were given and
0.0001 = 1.96*0.001/sqrt(n)
0.0001 = 0.00196/sqrt(n)
Solve for n
0.0001*sqrt(n) = 0.00196
sqrt(n) = 19.6
n = 4.427188724
Since you can't have a fractional value for n, then n should be at least 5 for a 95% confidence interval that the measured mean is within 0.0001 grams of the correct mass.</span>
