What are the numbers that are supposed to be plugged in?
Answer:
B. 252
Step-by-step explanation:
To find the answer, you have to use the formula to calculate the number of combinations as in this case, the order in which the objects are selected doesn't matter:
nCr=n!/r!(n-r)!
n= number of sample points: 10
r= number of sample points in each combination: 5
10C5= 10!/5!(10-5)!
10C5= 10!/5!*5!
10C5= 252
According to this, the answer is that you have 252 different ways to choose your school lunch.
Answer:
Her initial position was:
-29ft
Where we use the minus sign because this is below the ocean's surface.
Now we also know that she keeps descending at a rate of -29ft per minute, then if she keeps descending for t minutes, her position will be:
P(x) = -29ft - 29ft/min*t
Now, we also know that she does not want to descend more than 81ft below the ocean's surface, then we have the inequality:
P(x) ≥ -81ft
-29ft - 29ft/min*t ≥ -81ft
Now let's isolate t in one side:
- 29ft/min*t ≥ -81ft + 29ft = -52 ft
- 29ft/min*t ≥-52 ft
t ≤ -52ft/(- 29ft/min) = 1.79 min
Then the maximum amount of time that she can keep descending is 1.79 minutes.