Answer:
495 combinations of 4 students can be selected.
Step-by-step explanation:
The order of the students in the sample is not important. So we use the combinations formula to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.

How many combination of random samples of 4 students can be selected?
4 from a set of 12. So

495 combinations of 4 students can be selected.
Answer:
60%
Step-by-step explanation:
If there are 250 tables you can multiply it by 4 to work with 1000. This means you have to multiply the other table cloth numbers. 150 x 4 = 600. 100 x 4 = 400. Once you simplify you can get 40 white and 60 red out of 100. 60/100 = 60%.
Answer:
t = 3 arc cos(h/7)/π
Step-by-step explanation:
The equation h=7cos(pi/3 t) models the (h) height in centimeters after (t) seconds of a weight attached to the end of a spring that has been stretched and released. To solve the equation for t we will solve the equation step by step:
h=7cos(pi/3 t)
Step 1)
Divide both sides by 7
h/7 = 7cos(pi/3 t)/7
Now the equation becomes h/7=cos(pi/3 t)
Step 2)
h/7=cos(pi/3 t)
Now apply inverse cosine function:
arc cos (h/7) = pi/3 t
Step 3)
t = 3 arc cos(h/7)/pi
Thus t = 3 arc cos(h/7)/pi ....
240 miles
d=48(5) which equals 240