There are the same number of beans in each box. How many beans are there in one box?

Two times a number plus three times another number equals 4. three times the first number plus four times the other number is 7. find the numbers

How can i differentiate this equation?

Isabelle is mixing red and blue paint to make purple paint she adds 3/10 of a fluid ounce of red to 12/25 of a fluid ounce of blue to make 1 1/30 fluid ounces of purple how many fluid ounces of red paint ounces of red paint will she need to make 3 fluid ounces of purple paint