Part A:
There are 8 possible outcomes.
HHH
TTT
HTH
THT
TTH
HHT
THH
HTT
Part B:
There is 2 outcomes that consist of all head or all tails.
Part C:
You would expect about 6 students to get all head or all tails.
Hope this helps c:
An example for #1 would be that: 15 is divisible by 3, but not 9. every third multiple of 3, (9, 18, 27,...) is divisible by 9 because 9 is three times the size of 3.
For part two the first number that I thought of is 23.
Answer: Choice A
S9 = (9/2)*(2+26)
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The formula is
Sn = (n/2)*(a1+an)
where
Sn = sum of the first n terms (nth partial sum)
n = number of terms
a1 = first term
an = nth term
In this case,
n = 9
a1 = 2 (plug in n = 1 into the formula an = 3n-1 and simplify)
an = a9 = 26 (plug n = 9 into the formula an = 3n-1 and simplify)
So,
Sn = (n/2)*(a1+an)
S9 = (9/2)*(2+26)
will help us find the sum of the first 9 terms of this arithmetic sequence
Answer:
15x^2 - 12x^3
Step-by-step explanation:
A rectangular block has 3 parts that play into its volume. length, width and height. The question gives us length and width in the form of x and 3x, so height is what's missing.
It gives us a bit more information saying the sum of its edges is 20. We also have to ask how many lengths, widths and heights are there. That may be a bit hard to understand, but is you are looking at a block I could ask how many edges are vertical, just going up and down. These would be the heights. There are 4 total, and this goes the same for length and width, so 4*length + 4*width and 4*height = 20.
Taking that and plugging in x for length and 3x for width (or you could do it the other way around, it doesn't matter, you get:
4*x + 4*3x + 4*height = 20
4x + 12x + 4h = 20
16x + 4h = 20
4h = 20 - 16x
h = 5 - 4x
Now we have h in terms of x, which lets us easily find the volume just knowing x. To find the volume of a rectangular block you just multiply the length, width and height.
x*3x*(5-4x)
3x^2(5-4x)
15x^2 - 12x^3
Question doesn't give a specific value for x at all so you should be done there. Any number you plug in for x should get you the right answer
23% is maybe the percentage but if not then it maybe a little higher or lower
