Question
The average height of each student in a class of 30
students is 170 cm. If 6 new students joined the class, then the average height of the each student in the class increases by 5 cm. Find the average height of 6 new students who joined the class.Solution
Total height of 30 students of the class = 170 × 30 = 5100 cm When 6 new students joined the class, average height of each student = 170 + 5 = 175 cm Total height of 36 students of the class = 175 × 36 = 6300 cm Average height of 6 new students who joined the class = {(6300 – 5100)/6} = 1200/6 = 200 cm
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