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nth term explanation maths

3 10 17 23
7n - 4
is 150 a term of this sequence?
Explanation :
7n - 4 = 150
Yes as 10 ends in 0, 150 also ends in 0 so 150 is in the sequence.

Is this worth 2 marks ? ( The explanation )
Well no. You are supposed to prove that n is an integer to satisfy the nth term
Reply 2
What i would say is 7n-4=150 so 7n=154 154/7 = 22 so yes it is the 22nd term of the sequence
Reply 3
Original post by dh12345
What i would say is 7n-4=150 so 7n=154 154/7 = 22 so yes it is the 22nd term of the sequence


oh
thanks man
Original post by Divinchi
3 10 17 23
7n - 4
is 150 a term of this sequence?
Explanation :
7n - 4 = 150
Yes as 10 ends in 0, 150 also ends in 0 so 150 is in the sequence.

Is this worth 2 marks ? ( The explanation )


It's a very simple explanation that doesn't show how you worked it out. Here is the one for 2 marks:

7n - 4 = 150
+4 +4
7n = 154
/7 /7
n = 22
Yes it is in sequence.
Reply 5
Original post by Divinchi
oh
thanks man


how would u explain it if it isnt?
Reply 6
Original post by Divinchi
how would u explain it if it isnt?


Showing it isn't an integer should be sufficient, you could even give the terms either side of the number and show it is inbetween the two e.g if it asked you if 150 is a term you could say the 21st term is 148 and 22nd term is 154

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