Question
The average height of each student in a class of 15
students is 160 cm. If 6 new students joined the class, then the average height of the each student in the class increases by 4 cm. Find the average height of 6 new students who joined the class.Solution
Total height of 15 students of the class = 160 × 15 = 2400 cm When 6 new students joined the class, average height of each student = 160 + 4 = 164 cm Total height of 31 students of the class = 164 × 31 = 3444 cm Average height of 6 new students who joined the class = {(3444 – 2400)/6} = 1044/6 = 174 cm
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