The answer is 4 while rounding. If you need the exact answer, it is 4.019685039370
A = r² π
254.469 = r² π
r² = 254.469 : 3.14159
r² = 81.00866
r = 9.0048
C = 2 r π = 2 * 9.0048 * 3.14159 = 56.55 units
Answer:
- 3 hours
- 1 hour 45 minutes
- 300 miles
Step-by-step explanation:
1. The trains are moving toward each other at a total speed of 50 +20 = 70 miles per hour. Together, they cover the 210 mile distance in ...
time = distance/speed
time = 210 mi/(70 mi/h) = 3 h
The trains collide after 3 hours.
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2. The fly is closing with the freight train at a speed of 100 +20 = 120 miles per hour. Together, the fly and the train cover the initial 210 mile distance in ...
(210 mi)/(120 mi/h) = 7/4 h = 1 hour 45 minutes
The fly first meets the oncoming freight train after 1 h 45 min.
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3. The fly is flying for all three hours before the trains collide, so, at 100 miles per hour, will fly 300 miles.
Slope-intercept form: y = mx + b [m is the slope, b is the y-intercept or the y value when x = 0 ---> (0, y) or the point where the line crosses through the y-axis]
y = 25x + 125
"y" would represent the total amount of $ she has saved.
The y-intercept would be 125 or (0, 125), this means that she already/initially had $125 in her savings account, before she started depositing $25 per week
Answer:
79.77%
Step-by-step explanation:
P(X≥120) = normalcdf(120,1e99,130,12) = 0.7976716754 ≈ 0.7977 = 79.77%
Therefore, about 79.77% of operations last at least 120 minutes
