The average of 7 numbers is 60 . The average of the first three numbers is 50 , while the average of the last three is 70 . What must be the remaining number?
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Correct Answer: Option C
Explanation:
Sum of all the seven numbers \(=60^{\star} 7=420\)
Sum of the first three \(=50 \star 3=150\)
Sum of the last three \(=70^{\star} 3=210\)
Remaining Number \(=420-(210+150)=60\)
Sum of all the seven numbers \(=60^{\star} 7=420\)
Sum of the first three \(=50 \star 3=150\)
Sum of the last three \(=70^{\star} 3=210\)
Remaining Number \(=420-(210+150)=60\)