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:
A. -45
Step-by-step explanation:
multiplying a positive an a negative number gives out a negative result
so when we multiple 9 with -5 the result is -45
Answer:
x=4
Step-by-step explanation:
if you do
you'll get that
is 64.
Answer:
36.75
Step-by-step explanation:
First is turn the percent into a decimal which would be 0.35.
Then multiply 0.35 with 105
Finally this would equal to 36.75
Note: Hope I got it right, if I didn't I am very sorry this is all I can really do. If I did get it wrong please comment and I'll try again.
Answer:
y = 8
Step-by-step explanation:
Hello!
We can solve for y by isolating it.
<h3>Solve for y</h3>
- 3y - 15 = y + 1
- 3y - 15 - y = y +1 - y
- 2y - 15 = 1
- 2y - 15 + 15 = 1 + 15
- 2y = 16
- y = 16/2
- y = 8
The value of y is 8.