Katie is selling lemonade for $1.50 per cup. she decides to put them on sale for $0.90. what percent discount did she give on her lemonade

40%.

Step-by-step explanation:

The discount is 1.50 - 0.90 = $0.60.

Percent discount =(0.60 * 100) / 1.50

=  40%.

If she normally sells them for $1.50 per cup and she puts them on discount so that the price changes to $0.90 It would be 40% off I believe. The amount off would be $0.60 so the final price would be $0.90. Discount = Original Price x Discount %/100

Discount = 1.5 × 40/100

Discount = 1.5 x 0.4

You save = $0.60

Final Price = Original Price - Discount

Final Price = 1.5 - 0.6

Final Price = $0.90