An engineer needs to determine the distance across a river without swimming to the other side. The engineer notices a tree on th
1 answer:
Answer:
Step-by-step explanation:
The engineer can use a clinometer to measure the angle of elevation of the top of the tree. Let the height of the tree be represented by x, the she could determine the distance across the river, d, by applying the trigonometric function.
Tan θ =
=
the the distance, d = x ÷ Tan θ
Assume the angle of elevation of the top of the tree is , and the height of the tree is 10 m, then the distance, d, across the river would be;
d =
= 17.3190
d = 17.32 m
The sketch to the explanation is attached to this answer for more clarification.
You might be interested in
Answer:
a) 504
b) 56
c) 0.111
Step-by-step explanation:
Data provided in the question:
There are nine golf balls numbered from 1 to 9 in a bag
Three balls are randomly selected without replacement
a) 3-digit numbers that can be formed
=
n = 9
r = 3
= ⁹P₃
=
= 9 × 8 × 7
= 504
b) 3-digit numbers start with the digit 1
= _ _ _
in the above 3 blanks first digit is fixed i.e 1
we and we have 8 choices left for the last 2 digits
Thus,
n = 8
r = 2
Therefore,
= 1 × ⁸P₂
= 1 ×
= 1 × 8 × 7
= 56
c) Probability that the 3-digit number formed is less than 200
Now,
The number of 3-digit number formed is less than 200 will be the 3-digit numbers start with the digit 1 i.e part b)
and total 3-digit numbers that can be formed is part a)
therefore,
Probability that the 3-digit number formed is less than 200
= 56 ÷ 504
= 0.111