Answer:
<em>V = 1,568</em>
Step-by-step explanation:
<u>The Volume of a Square Pyramid</u>
Given a square-based pyramid of base side a and height h, the volume can be calculated with the formula:
We are given a square pyramid with a base side a=14 ft but we're missing the height. It can be calculated by using the right triangle shown in the image attached below, whose hypotenuse is 25 ft and one leg is 7 ft
We use Pythagora's theorem:
Solving for h:
The height is h=24 ft. Now the volume is calculated:
V = 1,568
1 cm = 20 km
so 3.5 cm would equal : 3.5 * 20 = 70 km <==
Let x be the length of the train.
On the basis of the observer;
Speed of the train = x/6
On the basis of the bridge;
Total distance covered by any point of the train= 350+x
Speed = (350+x)/20
Equating the two expressions of speed;
x/6 = (350+x)/20
20(x) = 6(350+x)
20x = 2100+6x
(20-6)x = 2100
14x = 2100
x= 2100/14 = 150 m
Speed = x/6 = (350+x)/20 = 150/6 = 500/20 = 25 m/s.
Therefore,
Length of train = 150 m
Speed of train = 25 m/s
6x-9=15
6x=24
x=4
Therefore the answer is A.
Hope this helps :)
