The average age of all the 100 employees in an office is 29 yr, where 2/5 employees are ladies and the ratio of average age of men to women is 5: 7. The average age of female employees is: একটি অফিসে 100 জন কর্মচারীর গড় বয়স 29 বছর, যেখানে 2/5 কর্মচারী মহিলা এবং পুরুষ ও মহিলাদের গড় বয়সের অনুপাত 5 : 7। মহিলা কর্মচারীদের গড় বয়স কত?

Total employees = 100

Average age = 29 years

\[ \text{Total Age} = 100 \times 29 = 2900 \]

Number of ladies = \( \frac{2}{5} \times 100 = 40 \)

Number of men = \( 100 - 40 = 60 \)

Ratio of average age of men : women = 5 : 7

Let average age of men = \( 5x \)

Average age of women = \( 7x \)

Total age equation:

\[ 60(5x) + 40(7x) = 2900 \]

\[ 300x + 280x = 2900 \]

\[ 580x = 2900 \]

\[ x = 5 \]

Average age of women:

\[ 7x = 7 \times 5 = 35 \]

Correct Answer: Option B