The regular price of an item is $150. the item is on sale at a discount rate of 30%.

what is the sale price of the item?

30/150=?/100. 30÷100=0.3. then 0.3×150=45

Since the discount is 30%, the item is selling at 70% of $150.
0.7x150=115
So the sale price is: $115

Alternatively, you could subtract 30% of 150 (which is 45) from 150 to get the same answer of 115.