Answer:I think it's 3 7.75/20 hours
Step-by-step explanation:
Multiply 2/15 by 20 (2x20 and 15x20)
Then 13/20 by 15 (13x15 and 20x15)
Subtract (195/300 - 40/300)
And you get 155/300
Then divide by 20 because dividing by 15 gives you 10.333333
So divide 155/300 by 20 (155÷20 and 300÷20)
And you get 7.75/20
Finally subtract the 2 hours from 5 hours and get 3 hours
Your answer is 3 7.75 hours
Answer: 3/7
Step-by-step explanation:
There's 28 student total.
12/28 simplify to 3/7
Another way is to note that there are <span><span>(<span>104</span>)</span><span>(<span>104</span>)</span></span> (“10 choose 4”) ways to select 4 balls from a collection of 10. If 4 of those 10 balls are “special” in some way (in this case, “special” = “red”), then the number of ways to choose 4 special balls is <span><span>(<span>44</span>)</span><span>(<span>44</span>)</span></span>. (The factor of <span><span>(<span>60</span>)</span><span>(<span>60</span>)</span></span> is included to convey that, after choosing 4 special balls, we choose none of the 6 non-special balls.) This line of reasoning gives the second expression.
Roll dice and flip coin:
Probability of rolling a cube and getting a 3 = 1/6 .
Probability of flipping a coin and getting HEADS = 1/2 .
Probability of both = (1/6) x (1/2) .
You do the multiplication.
4 blue, 2 green, 6 red
Probability of a blue on the first draw = 4 out of 12 marbles = 1/3 .
Without putting the blue back in ...
Probability of a red on the next draw = 6 out of 11 marbles = 6/11 .
Probability of both = (1/3) x (6/11) .
You do the multiplication.
