Answer:
755,160 ways
Explanation:
We're told that 31 cars are in a race.
Considering the order in which the cars can finish in the top 4 positions, any of the 31 cars can finish in the first position, any of the remaining 30 cars can finish in the second position, any of the remaining 29 cars can finish in the third position and any of the remaining 28 cars can finish in the fourth position, so the different numbers of ways can be determined as seen below;
Answer:
3. rolling a sum of 20 with two standard dice
Step-by-step explanation:
If something has a probability of 0 then there is no chance of it happening
A standard die goes up to 6. The max sum you can get by rolling two dice would be 12 as 6 + 6 = 12. So you have no chance of rolling a sum of 20 with two standard dice therefore the probability would be 0.
Connie + 1 friend +2 friend = 10
3 people = 10 miles
3 people/3= 10 miles / 3
Each friend rode 3 1/3 miles
Answer: choice A. 40 liters
====================================
Explanation:
x = number of liters of the 50% alcohol solution
If we have x liters of 50% alcohol, then we have 0.50*x liters of pure alcohol. This is added to 0.90*40 = 36 liters of pure alcohol (from the 90% solution).
So far we have 0.50*x + 36. This expression represents the total amount of pure alcohol. We want a 70% solution, so we want 70% of the total 40+x meaning 0.50*x + 36 is to be set equal to 0.70*(40+x) and we solve for x as shown below
0.50*x + 36 = 0.70*(40+x)
0.50*x + 36 = 0.70*(40)+0.70*(x)
0.50*x + 36 = 28+0.70*x
36 - 28 = 0.70*x - 0.50x
8 = 0.20x
0.20x = 8
x = 8/0.20
x = 40
So that is why the answer is choice A. 40 liters
