Are these really 70% off?

We ran into this sale online.

Is that advertisement correct?  Do they just want us to believe their math and not question what is really 70% off?  Is everything or anything really 70% off?

The activity:  Is-anything-really70%off?.pdf

CCSS: 6.RP.3, 6.RP.A, 7.RP.3, 7.RP.A

For members we have an editable Word docx, a PowerPoint presentation of the lesson, and solutions/teacher thoughts.

Is-anything-really70%off?.docx      is-anything-really-70-off.pptx      70%-off?-solutions.pdf

from Yummy Math http://www.yummymath.com/2016/are-these-really-70-off/