The answer is B.33, this is because the numbers are increasing by 2's. (+2,+4+,+6, ect.)
Answer: -9n+20
This is the same as 20-9n
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Explanation:
The jump from 11 to 2 is "minus 9"
The jump from 2 to -7 is also "minus 9".
Assuming this pattern continues on, we have an arithmetic sequence with
- a = 11 = first term
- d = -9 = common difference
The nth term can be found like so
Let's check the answer by trying n = 3
This shows the third term is -7, which matches what the original sequence shows. The answer is partially confirmed. I'll let you check the other values of n. You should get 11 when trying n = 1, and you should get 2 when trying n = 2.
One quarter. Because four quarters makes a whole.
24
We can divide the 8th graders into 4 groups. They are:
1. Like both math and science.
2. Like only math.
3. Like only science.
4. Don't like either math or science.
The sum of the people in all 4 groups will add up to 120. So let's see how many are in each group.
We've been given 23 as the number of people who like only math (group 2).
And since we know that 84 people like math, that means that 84 - 23 = 61 people are in group 1. And since we know that 73 people like science, that means that 73 - 61 = 12 are in group 3. So of the 4 groups, we now know.
1. Like both math and science (61 people).
2. Like only math (23 people).
3. Like only science (12 people).
4. Don't like either math or science (unknown).
So for the people left in group 4 (don't like either subject) that will be 120 - 61 - 23 - 12 = 24.
