What does grouping mean in math im confused

Harry’s soccer team plays 2 nonconference games for every 3 games that they play against conference opponents. if y represents the number of nonconference games and x represents the number of conference games, which equation best models this proportional relationship? a)y=2/3 x b)y=3/2 x c)y = 2x d)y = 6x

If 1/2+2/5s=s-3/4,what is the value of s? a. s=3/4 b. s=25/12 c. s=-25/12 d. s=-3/4

What is the area of a pizza with a radius of 40 cm leave the answer in terms of π to find your exact answer 40π cm² 1600π cm² 800π cm² 80π cm² π=pi