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3 years ago

9

the average height of a class of 18 students is 105cm. After the arrival of 7 new students the average decreases by 5cm. Find su

m of the heights of all the students in the class

1 answer:

Marizza181 [45]3 years ago

5 0

Step-by-step explanation:

18+7=105-5

25/25=100/25

4

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