Each lap of the track at oak middle school is 1/4 of a mile. jacob jogged around the track and completed 9 laps in 30 minutes.

what is the unit rate of jacob's speed?

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of

Solve for x: 5/3 x = 20/21 it's fraction. remember to simplify your fraction

Pls the last one and it has to be like number 6