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:
The answer should be 5 or -5
Answer:
Step-by-step explanation:
Using the change of base rule for logarithms
x = 
( where c is the new base )
Given
log 17 , that is 
17 , then
17 =
Answer:
x = 129°
Step-by-step explanation:
∠ ABD and ∠ DBC are a linear pair and sum to 180° , then
y + ∠ DBC = 180°
107° + ∠ DBC = 180° ( subtract 107° from both sides )
∠ DBC = 73°
the exterior angle of a triangle is equal to the sum of the 2 opposite interior angles , then
x = ∠ DBC + z = 73° + 56° = 129°
First you do 7.9/ 1/4, that gets you 1.975. that is how much blue paint there is. Then you do 7.9-1.975= 5.925, which is how much white paint she used. So in total she used 1.975 pints of blue paint, and 5.925 pints of white paint.
