Question

the average age of 17 teachers of a school was 45 .two teachers of age 55 retired and instead two teachers with ages 34 and 42 were joined. what is their present average age?​

Answer 1

Step-by-step explanation:

Average age of 17 teachers = 45

Average = Sum of Ages / No of teachers

45 = Sum of ages / 17

45 × 17 = Sum of Ages

765 = Sum of Ages

Two teachers of 55 age retired

55 × 2 = 110

Then, Sum of Ages is :

765 - 110 = 655

Two teachers with 34 and 42 ages were joined

34 + 42 = 76

Then, Sum of Ages is :

655 + 76 = 731

Then, the Present Average Age of teachers is :

Average = Sum of Ages / No of teachers

= 731 / 17

= 43