Concept: The question tests on the area of Probability
Probability of drawing a red ball = 7/11 and probability of drawing a blue ball = 4/11
When drawing with replacement, order matters, which means we can have red first and blue second, or blue first and red second.
P(RB) = 7/11 * 4/11 = 28/121
P(BR) = 4/11 * 7/11 = 28/121
The required probability = 28/121 + 28/121 = 56/121