Answer:
B
Step-by-step explanation:
a. Notice that
1/(1*2) = 1/2 = 1 - 1/2
1/(2*3) = 1/6 = 1/2 - 1/3
1/(3*4) = 1/12 = 1/3 - 1/4
and so on, which suggests the n-th term of the sum can be written as
Then the sum itself is telescoping:
b. The proof is trivial:
so the formula found in (a) is correct.
Answer:
a) 0.75
b) 0.0625
c) 0.1875
d) 0.375
Step-by-step explanation:
Let's start by first finding the probability a teacher orders 6 boxes. Since it is a four sided dice, the probability of getting a 1 is going to be 0.25.
Similarly, for any other number on the dice, the teacher orders 2 boxes. We can think of this as NOT rolling a 1. Using our previous answer, this comes out to be: 1 - 0.25 = 0.75
It should be remembered in the following answers that teachers ordering 6 or 2 boxes are not influenced by the results of other teachers. These are statistically independent events.
a) As given above, this probability is 0.75
b) The probability that both teachers order 6 boxes will be their individual probabilities multiplied. This comes out to be: 0.25 x 0.25 = 0.0625
c) Like in part (b), this is both of their probabilities multiplied:
0.25 x 0.75 = 0.1875
d) This is nearly the same as part (c), but with a little twist. The order matters. There are two scenarios:
- First teacher gets 6 boxes, and the second gets 2.
- First teacher gets 2 boxes, and the second gets 2.
Both of these events have a probability of 0.1875, as shown in (c). To get the total probability of this event happening, we must add these together:
0.1875 + 0.1875 = 0.375
First thing you would do is distribute the negative on the outside of the parentheses to the inside terms:
9x - 5x + 7 = 39
Now, combine like terms:
4x + 7 = 39
Subtract 7 from both sides to get variables on one side of the equal sign and constants on the other:
4x = 39 - 7
4x = 32
Divide both sides by 4 to isolate the variable x.
x = 32 / 4
x = 8
C: 20 m/s
Explanation:
Distance run: 1000m
Time passed: 50s
Distance divided by time equals speed.
1000m / 50s = 20 m/s
