Question
The average height of each student in a class of 30
students is 100 cm. If 6 new students joined the class, then the average height of the each student in the class increases by 3 cm. Find the average height of 3 new students who joined the class.Solution
Total height of 30 students of the class = 100 × 30 = 3000 cm When 6 new students joined the class, average height of each student = 100 + 3 =103 cm Total height of 36 students of the class = 103 × 36 = 3708 cm Average height of 6 new students who joined the class = {(3708 – 3000)/6} = 708/6 = 118 cm
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