Answer:
33.04% probability that exactly five of them are black
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
The order in which the buttons are chosen 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.

Desired outcomes:
Five black buttons, from a set of 10
Four brown buttons, from a set of 6.

Total outcomes:
Nine buttons, from a set of 16.

Probability:

33.04% probability that exactly five of them are black
a) 24% said they wanted to learn french.
To find total number of students surveyed divide the number of students that want to learn French by the percentage:
12 / 0.24 = 50
There were 50 students surveyed.
b) 36% wanted to learn Spanish, multiply 50 by 36%
50 * 0.36 = 18
18 students wanted to learn Spanish.
Answer:
gallons = dependent
minutes = independent
Step-by-step explanation:
independent variable = the variable being manipulated/changed
dependent variable = the variable being changed as a result
gallons = dependent (of the minutes of running water)
minutes = independent (affecting the gallons)
P = √ab
p² = ab
p²/b = a
a = p²/b
Answer:
Step-by-step explanation:
In step one she has added 1x to each side of the statement
in step two she has taken five away from both sides of the equation therefore simplifying the entire equation
in step three she divided both sides by three to have the unknown value on one side of the equation