Question
The average height of each student in a class of 10
students is 166 cm. If 2 new students joined the class, then the average height of the each student in the class increases by 7 cm. Find the average height of 2 new students who joined the class.Solution
Total height of 10 students of the class = 166 × 10 = 1660 cm When 2 new students joined the class, average height of each student = 166 + 7 = 173 cm Total height of 12 students of the class = 173 × 12 = 2076 cm Average height of 2 new students who joined the class = {(2706 – 1660)/2} = 416/2 = 208 cm
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