n(n+1)
The difference between the terms increases by 2 each time. 20-12=8 30-20=10 42-30=12 56-42=14 ... f(n)=(n+2)(n+3)
Looks like 57: 12+9=21, +9=30, +9=39, +9=48, +9=57.
This is an arithmetic progression. In general, If an A.P. has a first term 'a', and a common difference 'd' then the nth term is a + (n - 1)d. In the sequence shown in the question, the first term is 0 and the common difference is 5, therefore the nth term is, 0 + (n - 1)5. This can be rearranged to read : 5(n - 1) For example : the 7th term is 30 : 5(7 - 1) = 5 x 6 = 30.
6n+10
n(n+1)
The difference between the terms increases by 2 each time. 20-12=8 30-20=10 42-30=12 56-42=14 ... f(n)=(n+2)(n+3)
> since the value rises by nine at each step and the first term is 12 the formula for > the nth term is: 12+(n-1)*9 Which simplifies to Sn = 9n + 3
Say if you had the pattern 15 20 25 30 35 40 45 50 To find the nth term you have to see what the gap between the numbers is. In our case this is 5. Then you have to find out what the difference between the gap and the first number. In this sequence it is 10. So your answer would be..... 5n+10 That's how you find the nth term.
Clearly here the nth term isn't n25.
90
Looks like 57: 12+9=21, +9=30, +9=39, +9=48, +9=57.
This is an arithmetic progression. In general, If an A.P. has a first term 'a', and a common difference 'd' then the nth term is a + (n - 1)d. In the sequence shown in the question, the first term is 0 and the common difference is 5, therefore the nth term is, 0 + (n - 1)5. This can be rearranged to read : 5(n - 1) For example : the 7th term is 30 : 5(7 - 1) = 5 x 6 = 30.
6n+10
When n=30, 3n-1 = 89 .
The nth term is 7n-5 and so the 6th term will be 37
Just plug in 30 for n in 3n-1. The answer is 89.