Becky, Markus and Halle each earned $2.15 raking leaves. How much did the earn together?

What number produces an irrational number when multiplied by -1.25

Me with this one question, and i'll upvote the brainliest answer

Danielle earns a 7.25% commission on everything she sells at the electronics store where she works. she also earns a base salary of $750 per week. what were her sales last week if her total earnings for the week were $1,076.25?