Answer:
33,33%
Step-by-step explanation:
In order to calculate this you just need to figure out how much does the money that is being removed from the cost is in percentage, we know that the notebook costs 1.20 each, and they are on sale for .80, so to calculate the difference we withdraw from the total cost, the sale cost:
1,20-,80=,40
So the disscount is ,40 dollars, now we use a rule of three to calculate this, using 1,20 as the 100%:
![\frac{1,20}{100}= \frac{,40}{x} \\x=\frac{100*,40}{1,20}\\ x=33,33333](https://tex.z-dn.net/?f=%5Cfrac%7B1%2C20%7D%7B100%7D%3D%20%5Cfrac%7B%2C40%7D%7Bx%7D%20%5C%5Cx%3D%5Cfrac%7B100%2A%2C40%7D%7B1%2C20%7D%5C%5C%20x%3D33%2C33333)
So we get that the percentage of the disscount will be 33.33%