Question 1151346
<br>
7+2=9; 9-4=5
5+2=7; 7-4=3
3+2=5; 5-4=1
1+2=3; 3-4=-1<br>
The apparent pattern is "add 2, subtract 4, repeat".  So the most probable next number in the sequence is<br>
-1+2=1<br>
Alternatively, separate the given sequence into two spliced sequences:<br><pre>
7   5   3   1  -1
  9   7   5   3   x<br></pre>
In each sub-sequence, the pattern is to repeatedly subtract 2.  That means the next number (in the second sub-sequence) is 1.<br>