The sum of the three numbers is 123. If the ratio between the first and second is 3: 4 and that between the second and third is 3: 5, then find the second number.

Correct option is D

Given:
The sum of the three numbers = 123
Ratio between the first and second numbers = 3:4
Ratio between the second and third numbers = 3:5
Solution:
Let the three numbers be A, B, and C.
Let the second number (B) be 12x, so:
- First number A = (3/4) × B = (3/4) × 12x = 9x
- Third number C = (5/3) × B = (5/3) × 12x = 20x
The sum of the three numbers: A + B + C = 9x+ 12x+ 20x 
41x = 123
x = 3
Thus, the second number B = 12x = 12 × 3= 36.