Question 526363
( sum of 1st 3 numbers )/3 = 9 
sum of 1st 3 numbers  = 27 
and
( sum of next 7 numbers ) / 7 = 30 
sum of next 7 numbers = 210 
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sum of all 10 numbers = 27 + 210
sum of all 10 numbers = 237
average of 10 numbers = 237/10
237/10 = 23.7