Answer:
1120 combinations of four teachers include exactly one of either Mrs. Vera or Mr. Jan.
Step-by-step explanation:
The order in which the teachers are chosen is not important, which means that the combinations formula is used to solve this question.
Combinations formula:
is the number of different combinations of x objects from a set of n elements, given by the following formula.
In this question:
1 from a set of 2(Either Mrs. Vera or Mr. Jan).
3 from a set of 18 - 2 = 16. So

1120 combinations of four teachers include exactly one of either Mrs. Vera or Mr. Jan.
Answer:
4 7/8
Step-by-step explanation:
First we need to gte the denominators the same!
So we multiply the 1/4 by 2
1/4 x 2 = 2/8
Now we subtract the 2/8 from 5 1/8 to get our answer :)
5 1/8 - 2/8 = 4 7/8
Your final answer will be 4 7/8 :)
Have a great day!
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X=2
because if you subtract 3x on both sides you end up with x=2 <span />
Answer:

Step-by-step explanation:
Given : 
To Find : Which represents the empirical formula for
?
Solution:
Definition of Empirical Formula - A formula that gives the simplest whole-number ratio of atoms in a compound.

To reduce it in simplest form
Divide the subscript numbers by 3
So, the resultant : 
Thus the empirical formula for
:

There was 12 benches because if you divided 72 by 6 you would get 12 if someone else answers please give brainliest