Answer:
# red marbles = 25
# blue marbles = 7
Step-by-step explanation:
r + b = 32
r = 4 + 3b
substitute '4 + 3b' for 'r' in the 1st equation
4 + 3b + b = 32
4 + 4b = 32
4b = 28
b = 7
red = 32 - 7
r = 25
Divide the pie chart into 10 pieces, then estimate to the best of your ability what percentage out of 100 that part is. Once completed multiply all of these percentages by 10 and this will be how many students in algebra, calculus, and geometry.
For the first marble would be: 2/11
For the second: 3/11