A class has 30 boys and 20 girls. The average age of boys is 12 yrs and girls 12 yrs. What is the
average age of the whole class."

Plz i beg u asap ! what is the equation of this graphed line? enter your answer in slope-intercept form in the box.

Which one ? is the answer and how to find this answer

Find the amount of simple interest earned for depositing the given principle in an account if $2200 is invested at 5.5 % for 6 months