Answer:
49 blue marbles
Step-by-step explanation:
From the question we are given;
We need to determine the number of blue marbles;
Assuming the number of red marbles is x
Then, blue marbles will be 5x + 4
Therefore;
x + 5x + 4 = 58
6x + 4 = 58
6x = 54
x = 9
5x + 4 = 5(9) + 4 = 49
Therefore, the red marbles are 9 while the blue marbles are 49
Hence there are 49 blue marbles