Answer:

Step-by-step explanation:
A standard die has six numbers (1 through 6). That means there is a 1/6 probability of rolling any one number. There is a 3/6 probability of rolling one of the selected numbers which simplifies to 1/2 or 0.50
Answer:
14 minutes below or 6 minutes above
Step-by-step explanation:
Let's say Sophia's time was 10 minutes WORSE
4 minutes below average- 10 minutes= 14 minutes below average
Let's say Sophia's time was ten minutes BETTER
4 minutes below average + 10 minutes= 6 minutes above average.
Hope this helps!
First of all, you add 1/3 and 4/5, so you get:

To add 2 fractions, they need to have the same denominator. Since 3 and 5 don't have a common factor, so you multiply 1/3 by 5, and 4/5 by 3, so you get:


Now, the two fractions got the same denominator, and you can add them by adding the numerators over the same denominator. (You don't add denominators in addition) so you get:


That's the sum of 1/3 + 4/5.
Now, they want the sum of the 2 fractions 7 times. So you multiply 17/15 by 7. And as you know, 7 = 7/1. So you get:

In multiplication no need to have the same denominator. You multiply nominators by nominators and denominators by denominators. So you get:


Since 119 and 15 don't have a common factor, so they can't be simplified.
So, the answer is 119/15.
Hope this Helps! :D
Answer:
0.80589
Step-by-step explanation:
So all of the numbers of correct answers less than 4 are 0,1,2,3
We need to calculate the probability for each separately and then add them together.
To find the probability we have to first find the combination. We know that there’s n=8 trials and that p=0.3. So 1-0.3 gives us 0.7.
The combination formula is: ! / (!(−)!)
So the n would always =8, and the r would be 0,1,2,3. So you would have to calculate it for 0,1,2,3 Separately. This can be done by hand or you can use a simple combinations calculator online.
For 0;
The combination is 1,
1 x 0.3^0 x 0.7^8-0 =
0.057648
For 1;
The combination is 8,
8 x 0.3^1 x 0.7^8-1 =
0.19765
For 2;
The combination is 28
28 x 0.3^2 x 0.7^8-2 =
0.296475
For 3;
The combination is 56
56 x 0.3^3 x 0.7^8-3 =
0.254122
All that’s left is to add these four numbers;
0.057647 + 0.19765 + 0.296475 + 0.254122 = 0.80589