JEE Main202523 Jan 2025Morning ShiftMathematicsProbabilityActual
One die has two faces marked 1 , two faces marked 2 , one face marked 3 and one face marked 4 . Another die has one face marked 1 , two faces marked 2 , two faces marked 3 and one face marked 4. The probability of getting the sum of numbers to be 4 or 5 , when both the dice are thrown together, is
Options
- A2 3
- B1 2
- C4 9
- D3 5
Correct answer
B. 1 2
Step-by-step solution
a = number or dice 1 b = number on dice 2 (a, b)=(1,3),(3,1),(2,2),(2,3),(3,2),(1,4),(4,1) Required probability aligned & = 2 6 2 6 + 1 6 1 6 + 2 6 2 6 + 2 6 2 6 + 1 6 2 6 + 2 6 1 6 + 1 6 2 6 & = 18 36 = 1 2 aligned