Tyra has 12 2/3 cups of sugar. If r is the amount of sugar called for in one batch of cookies, the expression 12 2/3 ÷ r can be used to find how many batches Tyra can make with the sugar she has. If r is 2/3 cup, how many batches of cookies can Tyra make? 19. Evaluate the expression for x = 1.7 x^2 + 3x. 7.99. Which of the ...