At first glance, it looks random, just numbers stacked one after another, but the moment you try to guess the next one, it doesn’t feel obvious, because this isn’t about simple counting, it’s about spotting the pattern hidden between the numbers
The sequence goes
10, 15, 25, 40, ?
Most people start guessing, adding random amounts, trying to jump ahead, but the key is to look at the difference between each step
From 10 to 15
That’s +5
From 15 to 25
That’s +10
From 25 to 40
That’s +15
Now the pattern becomes clear
The increases are growing by 5 each time
+5, +10, +15…
So the next step should be
+20
Now apply it
40 + 20 = 60
That’s the correct answer
60
Simple once you see it
But tricky enough to make most people stop and think.