im really behind in math what do i do im supposed to be in 8th going into 9th but in6th and still dont understand 6th

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

Astore sells two types of radios. one type sells $87 and the other for $119. if 25 were sold and the sales were $2495, how many of the $87 radios were sold a) 5 b) 20 c) 15 d)10

Mozart lenses inc. recently introduced seelites, a thinner lens for eyelasses. of a sample of 800 eyeglass wearers, 246 said they would purchases their next pair of eyeglasses with the new lenses. lenses inc. estimates that the number of people who purchase eyeglasses in a year is 1,700,000. most eyeglasses wearer buy one new pair of eyeglasses a year. what is the annual sales potential for the new lenses.