
import pandas as pd
import numpy as np

# Load the data into a DataFrame
df = pd.DataFrame({'Name': ['Ali', 'John', 'Gaurav', 'Raj', 'Ravi', 'Natasha', 'Aliya'],
                  'Age': [17, 17, 18, 17, 18, 17, 17],
                  'Gender': ['M', 'M', 'M', 'M', 'M', 'F', 'F'],
                  'Marks': [90, 76, np.nan, 74, 65, np.nan, 71]})

# Inspect the data
print(df.info())


mean = df['Marks'].mean()
df['Marks'] = df['Marks'].fillna(mean)
df