Why are they not equal? Please explain!!

Students buying lunch at rockwell elementary school yesterday chose either burritos or pizza. 185 students chose burritos and 252 chose pizza. 1. estimate the number of students who brought lunch by rounding each number to the nearest hundred. 2. estimate how many students bought lunch by rounding each number to the nearest ten. 3. find the total number of students who brought lunch. which of your estimates is closer to the actual total? explain. 4. draw a figure on a sheet of paper. estimate how many pennies will fit inside the figure. check your prediction using pennies.

An airplane consumes fuel at a constant rate while flying through clear skies, and it consumes fuel at a rate of 64 gallons per minute while flying through rain clouds. let c represent the number of minutes the plane can fly through clear skies and r represent the number of minutes the plane can fly through rain clouds without consuming all of its fuel. 56c+64r < 900056c+64r< 9000 according to the inequality, at what rate does the airplane consume fuel while flying through clear skies, and how much fuel does it have before takeoff? the airplane consumes fuel at a rate of gallons per minute while flying through clear skies, and it has gallons of fuel before takeoff. does the airplane have enough fuel to fly for 60 minutes through clear skies and 90 minutes through rain clouds?

Which of the points a(6, 2), b(0, 0), c(3, 2), d(−12, 8), e(−12, −8) belong to the graph of direct variation y= 2/3 x?