1.5 1.75 2 2.25 1.5 is a broken sequence, because of the last term. I believe it was meant to be a 2.5.
If it was written as 1.5, 1.75, 2, 2.25, 2.5 you could write all the terms as fractions with a common denominator of 4 to see.
6/4, 7/4, 8/4, 9/4, 10/4 to see 11/4 comes next, which is equal to 2.75.
Alternatively, you could just see that the decimal increases by 0.25 each time, which is the easiest way.
Start with 3 and multiply by 5 and 3 alternately in sequence.
The next number could be 26 The next number could be 12 - - - - - - - - - The next number that is in the sequence is 12.
152= 15*15 = 225 152= 15*15 = 225 152= 15*15 = 225 152= 15*15 = 225
15
425
7/9 of 225 is 175.
Start with 3 and multiply by 5 and 3 alternately in sequence.
The next number in the sequence 3-15-6-30-21 is -207.
The next number could be 26 The next number could be 12 - - - - - - - - - The next number that is in the sequence is 12.
5
152= 15*15 = 225 152= 15*15 = 225 152= 15*15 = 225 152= 15*15 = 225
.75
240
15
The number 225/15 means 225 divided by 15. The answer is 15.
5
425