Answer:
18.84 meters.
Step-by-step explanation:
The formula for a circle is πr^2.
πr^2 = 28.26
3.14 * r^2 = 28.26
r^2 = 9
r = plus or minus 3.
But since this deals with the area of a circle, there is no way a radius can be negative. So, the radius is 3 meters.
The formula for the circumference is 2πr.
2 * 3.14 * 3 = 6 * 3.14 = 18.84.
So, the circumference of the circle is 18.84 meters.
Hope this helps!
Answer:
8 seconds.
Step-by-step explanation:
To solve this question, we need to find the time, 
, when 
, that is, when the height of the object above the ground is 0 feet.
Substituting 
feet per second and gives the quadratic:
Since 128 is divisible by 16, it can be reduced to 
.
We must now solve for .
We can easily see that one answer to the equation is 0,
(we need not concern ourselves with the 16 outside of the parenthesis as in the equation above, since 16 multiplied by 0 is 0). However this is the time the object is released into the air.
The second answer, 
is also easy to see by inspection:
.
Therefore the object lands 8 seconds after it is thrown.
Answer:
option (b) 0.0228
Step-by-step explanation:
Data provided in the question:
Sample size, n = 100
Sample mean, μ = $20
Standard deviation, s = $5
Confidence interval = between $19 and $21
Now,
Confidence interval = μ ± 
thus,
Upper limit of the Confidence interval = μ +
or
$21 = $20 + 
or
z = 2
Now,
P(z = 2) = 0.02275 [From standard z vs p value table]
or
P(z = 2) ≈ 0.0228
Hence,
the correct answer is option (b) 0.0228
You’re right, both of the pairs are similar
Answer:
- 1 bus, 72 vans
- $6960 is the minimum cost
Step-by-step explanation:
A bus costs over $19 per student; a van costs less than $12 per student. The required number of students could be transported by 81 vans, but that requires 81 chaperones.
Since there are only 80, and a bus requires fewer chaperones per student, we can reduce the number of required chaperones to an acceptable level by employing one bus. 1 bus replaces 9 vans, and requires 1 less chaperone than 9 vans.
The minimum cost is 1 bus and 72 vans. That cost is $1200 +72×$80 = $6960.
