Question
The average height of each student in a class of 20
students is 125 cm. If 10 new students joined the class, then the average height of the each student in the class increases by 11 cm. Find the average height of 10 new students who joined the class.Solution
Total height of 20 students of the class = 125 times; 20 = 2500 cm When 10 new students joined the class, average height of each student = 125 + 11 =136 cm Total height of 30 students of the class = 136 times; 30 = 4080 cm Average height of 6 new students who joined the class = {(4080; 2500)/10} = 1580/10 = 158 cm
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