• # question_answer A group of 10 items has A.M 6, if the arithmetic mean of 4 of these items Is 7.5 the of the remaining items is: A)  5                    B)  3                C)  3.5                               D)  4.5

[a] $\because$Sum of 10 item $=6\times 10=60$             Sum of 4 item $=4\times 7.5=30.0$ Sum of remining 6 items $=60-30=30.$ Mean of remaining 6 items $=\frac{30}{6}=5$