All triangles interior angles equal 180
So these 3 angles = 180
Answer:
A (52,2%, 55,8%)
Step-by-step explanation:
To get the confidence interval, we have to add the margin of error to the point estimator.
The middle of the interval is 54%, and the ME is 1.8%. Don't forget that this means ±1.8%!
54 - 1.8 = 52.2%
54 + 1.8 = 55.8%
So our confidence interval is (52,2%, 55,8%) and the answer is A.
Surface area = 2(ab+bc+ac)
a=5.2 ft, b=2.4 ft, c=3.5ft
Surface area = 2(5.2 * 2.4 + 2.4 * 3.5 + 3.5 * 5.2) =
2(12.48 + 8.4 + 18.2) =
2 * 39.08 =
78.16 ≈ 78.2 ft² ← <span>to the nearest tenth</span>
If you mean 3 divided by 2 power 0 then the answer is 3
Answer:
- train: 40 kph
- plane: 140 kph
Step-by-step explanation:
Let t represent the speed of the train in km/h. Then 4t-20 is the speed of the plane. Travel times are the same, so we can use the formula ...
time = distance/speed
and equate the travel times.
110/t = 385/(4t-20)
Cross multiplying gives ...
110(4t -20) = 385t
440t -2200 = 385t . . . . . eliminate parentheses
55t -2200 = 0 . . . . . . . . . subtract 385t
t -40 = 0 . . . . . . . . . divide by 55
t = 40 . . . . . . . . . . . add 40; train's speed is 40 kph
4t -20 = 140 . . . . . . find plane's speed; 140 kph
The train's speed is 40 km/h; the plane's speed is 140 km/h.
_____
<em>Check</em>
Train's travel time = 110 km/(40 km/h) = 2.75 h.
Plane's travel time = 385 km/(140 km/h) = 2.75 h.
