The average age of a class of 32 students is 16 yrs. If the teacher's age is also included, the average increases by one year. Find the age of the teacher.
Students total age = 32×16 = 512 years
include teacher's age = 33 × (16+1) = 561
561-512 = 49 Yrs
In a class, the average age of 30 boys is 13 years and the average of 20 girls is 12 years. What is the average age of the whole class
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