<em>Answer:</em>
n²+3
<em>Explanation:</em>
The differences between the terms are not the same, so this is not "linear". Knowing that the sequence may have started with a 1, you can try subtracting the first number with a number to get 1, and use that number to subtract the rest.
4 - 3 = 1
7 - 3 = 4
12 - 3 = 9
19 - 3 = 16
28 - 3 = 25
In this case, subtracting 3 to all the numbers gave us perfect squares! So this means the nth term has to do with squaring the number and adding three afterward! This can be checked.
√1 = 1
√4 = 2
√9 = 3
√16 = 4
√25 = 5
As we found the values of these terms by subtracting three first and then finding its square root, the nth term will be the opposite; squaring and then adding three! Again, this can be checked!
1² + 3 = 4
2² + 3 = 7
3² + 3 = 12
4² + 3 = 19
5² + 3 = 28
Hope this helps !! :D
Answer:
The answer is,
Step-by-step explanation:
Firstly, you have to get rid of fraction by multiplying (r-3) to both side and expand out:
t × (r-3) = r/(r-3) × (r-3)
rt - 3t = r
Then you have to move all the "r" variables to one side and other variables to the other side:
rt - r = 3t
You can make "r" as a subject by taking out the common term, you can see that the common term on the left is "r" so you can bring out:
r(t-1) = 3t
r = 3t/(t-1)
The answer would be 12 students. 8+4+6+3=21.
84 divided by 21 would = 4.
3 students times 4 = 12 students
