Answer:
50 marbles
Step-by-step explanation: The difference between the ratio of the red and green marbles is 4 units and the number value is 20 so its safe to say that 4 units is equal to 20 and thus one unit is 5 and because of the fact that there is a total of 10 units of marbles in the box according to the ratio, just multiply 5 and 10 which you get 50.
4 units = 20
1 unit = 20÷4 = 5
Total = 10 units
10 unit = 5 ×10 = 50
Ans : 50 marbles
It’s order of operations it’s really easy
P- parentheses
E-exponents
M- multiply
D- divide
A- addition
S- subtraction
Do the problems in that order and u will get it answer
40 square units 10+10+10+10