Let x be that number.
"150% of" means 150% multiplied by. And 150% = 150/100.
So (150/100)x = 36.
1.5x = 36
Then, you divide each side by 1.5 so you can get x alone on a side, and the number on the other.
(1.5x)/1.5 = 36/1.5
x= 24.
So 36 is 150% of 24.
Hope this Helps! :)