Answer:
If there is 1 at the top, then you have 1, then 2, then 3, etc.
total number of oranges equals:
1 + 2 + 3 + ... + 16 + 17 + 18 <-- stop at 18 because this is the number of oranges at the base
You can use the formula:
sum of first n numbers = n*(n + 1)/2
-->
18*19/2 = 9*19 = 171
or you can figure it out (basically derive the above formula):
you have:
1 + 18 = 19
2 + 17 = 19
3 + 16 = 19
...
How many pairs do you have? Well, it's just the number of numbers: 1-18 = 18 numbers (divide by 2) = 9 pairs)
9 pairs of 19 = 9 * 19 = 171
Hope this helps!
Step-by-step explanation:
Answer:
For 99% of confidence interval is 67.5±1.3524
Step-by-step explanation:
Given:
Mean height =67.5 inches
Standard deviation:2.1 inches
Z at 99%.
No of samples 16.
To find:
confidence interval
Solution:
We have formula for confidence interval,
=mean ±Z*{standard deviation/sqrt(no.of observation)}
Now
Z=99%
has standard value as ,
Z=2.576
Confidence interval= mean±Z{standard deviation/sqrt(No. of samples)}
=67.5±2.57{(2.1/sqrt(16)}
=67.5±2.576(2.1/4)
=67.5±1.3524
Answer:
<h3>-3</h3>
Step-by-step explanation:
For two parallel lines. their slope are equal
Find the slope of each of the lines
For line A;
m = 0 -y/0+1
mA = -y/1
For line B;
mB = 9 - 3/8 - 6
mB = 6/2
mB = 3
since their slope are equal hence mA = mB
-y/1 = 3
-y = 3
y = -3
Hence the value of y is -3
To find which ratio is higher, we can first convert the ratios into fractions (that makes it easier, at least for me) and then simplify the fractions and see which one is greater.
Since ratios are basically division, 15:20 = 
, and
12:16 = 
Now we simplify these fractions. 15 and 20 have a GCF of 5, so taking out the common number gives us the simplified fraction of 
.
12 and 16 have a GCF of 4, so taking out the common number gives us the simplified fraction of . Since = , these ratios are the same.
Answer:
n-3
Step-by-step explanation:
Notice that the output is always 3 less than the input
output is input -3
f(n) = n-3
