Answer:
The number of red marbles in the bag are 114.
Explanation:
Given:
Total marbles in the bag is 120. There are 19 marbles for every black marble.
Now, to get how many red marbles in the bag.
Let the black marbles be
.
And the red marbles be
.
According to question:


Dividing both sides by 20 we get:


Black marbles = 6
So, the red marbles = 19×6 = 114.
Therefore, the number of red marbles in the bag are 114.