Step 1: From statement I, the ratio of the present ages of P and Q is 3:4. Let the present ages of P and Q be \( 3x \) and \( 4x \), respectively.
Step 2: From statement II, the ratio of the present ages of Q and R is 4:5. Let the present ages of Q and R be \( 4y \) and \( 5y \), respectively.
Step 3: We have two variables \( x \) and \( y \), and no further relationship is provided between \( x \) and \( y \). Therefore, we cannot determine the ratio of P’s and Q’s ages four years ago with the information given in both statements. Thus, the answer is \( \boxed{{C}} \).
If the probability distribution is given by:
| X | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|---|
| P(x) | 0 | k | 2k | 2k | 3k | k² | 2k² | 7k² + k |
Then find: \( P(3 < x \leq 6) \)
If \(S=\{1,2,....,50\}\), two numbers \(\alpha\) and \(\beta\) are selected at random find the probability that product is divisible by 3 :