Answer:
The value of cos Ф is ±
Step-by-step explanation:
There are important rules for sin Ф and cos Ф
∵ sin Ф =
∴ sin²Ф =
∴ sin²Ф =
→ By using the third rule above
∵ cos²Ф = 1 - sin²Ф
∴ cos²Ф = 1 -
∴ cos²Ф =
→ Take square root for both sides
∴ cos Ф = ±
∴ The value of cos Ф is ±
Answer:
50 students
Step-by-step explanation:
Hello!
To solve this question, we would first need to look at the data. In this data, there are people who chose their favorite sport, and the number of people who chose that response. In order to solve the problem, we would have to find the ratio of how many people choose baseball over the other sports.
By this, we can add the number of students together. 30+10+5+15=60. Out of those 60 students, only 5 people chose baseball.
Since the ratio of the people who chose baseball is 5/60 (meaning that it is a 5/60 % chance someone would pick this sport), we would need to find the amount of people assumed to pick baseball in 600 student survey.
We can make a relationship with these two numbers.
, since the ratio of the students who chose baseball remain the same.
You can see that the ratio on the denominators just add a zero on the bottom, so the top should add 0 as well, to get 50 for x, what we needed.
You can also solve that relationship by cross multiplication.
5(600)=x(60
3000=60x
50=x
Regardless, the answer is 50 students who would choose baseball in a 600 persons survey.
