Answer:
h = 7.5 foot
Step-by-step explanation:
Given that,
John has a 10 foot ladder leaning against a wall at an angle of elevation of 53.13 degrees.
We need to find the height where the ladder meet with the wall.
Let Perpendicular = 10 foot
Angle of elevation,
Let h be the height (Hypotenuse). Using trigonometry,
So, the ladder will meet the wall at a height of 7.5 foot.
When you solve fractions and you end up having an improper fraction so you simplify. So you get a mixed fraction. So to convert an improper fraction to the mixed one you simply divide the numerator by denominator. simple.
To evaluate the combination we proceed as follows:
21C3
Given nCk we shall have:
n!/[(n-k)!k!]
thus plugging the values in the expression we get:
21!/[(21-3)!3!]
=21!/(18!×3!)
=1330
Answer: 1330