Help please! Ron has 75 blue marbles and 125 red marbles. Enter the percent of blue marbles as a part of all marbles.

To write this is a percent, we need to put the blue marbles as the numerator and the total marbles on the denominator (blue marbles/total marbles). To find how much marbles there is, we add the amount of Rev marbles to blue marbles. 75+125=200. 75/200 =0.375 Writing it as a percent => 37.5%. Hope this helps :)