Answer:
confusion maxed out
Step-by-step explanation:
<u>650 cannonballs
</u>
Explanation step by step:
upper layer = 1 ^ 2
second layer = 2 ^ 2
third layer = 3 ^ 2
layer 12 is 12 ^ 2
<u>The formula is:
</u>
<u>n * (n + 1) * (2n + 1) / 6
</u>
<u>n = 12
</u>
<u>12 (12 + 1) (2 * 12 + 1) / 6
</u>
<u>12 * 13 * 25/6 =
</u>
<u>650
</u>
<u>
</u>
There are 650 cannonballs in this pyramid.
Ok so we'll go ahead and solve for y first - we just need to get it alone on one side of the equal sign
Step 1: subtract 2x from each side
2x - 7y - 2x = 19 - 2x
This cancels out the 2x on the left, giving us
-7y = 19 - 2x
Step 2: divide both sides by -7
=
+ 
This gives us
y = -19/7 + 2x/7
That should be your answer for the first question. Now solving the next parts are easy. All you need to do is plug in x.
When x = -3
y = -19/7 + 2x/7
y = -19/7 + 2(-3)/7
y = -19/7 - 6/7
y = -25/7
When x = 0
y = -19/7 + 2x/7
y = -19/7 + 2(0)/7
y = -19/7
When x = 3
y = -19/7 + 2x/7
y = -19/7 + 2(3)/7
y = -19/7 + 6/7
y = -13/7
Hope that helps! Feel free to ask if I can help with anything else :)
Answer:
The probability that the sample proportion is between 0.35 and 0.5 is 0.7895
Step-by-step explanation:
To calculate the probability that the sample proportion is between 0.35 and 0.5 we need to know the z-scores of the sample proportions 0.35 and 0.5.
z-score of the sample proportion is calculated as
z=
where
- p(s) is the sample proportion of first time customers
- p is the proportion of first time customers based on historical data
For the sample proportion 0.35:
z(0.35)=
≈ -1.035
For the sample proportion 0.5:
z(0.5)=
≈ 1.553
The probabilities for z of being smaller than these z-scores are:
P(z<z(0.35))= 0.1503
P(z<z(0.5))= 0.9398
Then the probability that the sample proportion is between 0.35 and 0.5 is
P(z(0.35)<z<z(0.5))= 0.9398 - 0.1503 =0.7895
Answer:
5 x 4 + 2 - 3 / 1
Step-by-step explanation:
Took me a lot of tries but got it! :) Hope this helps