Question

The probability, that in a randomly selected $3$-digit number at least two digits are odd, is

• A. $\frac{19}{36}$
• B. $\frac{15}{36}$
• C. $\frac{13}{36}$
• D. $\frac{23}{36}$

Answer 1

Answer: (A)

At least two digits are odd
= exactly two digits are odd + exactly there 3 digits
are odd
For exactly three digits are odd

For exactly two digits odd :
If 0 is used then $:2\times 5\times 5=50$
If 0 is not used then $:{}^3{C}_1\times 4\times 5\times 5=300$
Required Probability $=\frac{475}{900}=\frac{19}{36}$