A 20 pound mixture of salt water is 5% salt. How many pounds of water must be added to make it 3% salt?

Change negative exponents to positive. then solve. round to four decimal places

Why can't my rank go i have 1723 points, but my rank is only at ambitious, which is only 250 points! like, (p.s. i know this isn't related to math, but i just don't know why it's doing this and i would really appreciate if someone could tell me whats going on with this)

If the alternate hypothesis of an experiment is “the true mean height of the giraffes is more than 15 feet” what is the null hypothesis?