The average is 15.
(12+15+18)/3 = 15
The average is 15.
(12+15+18)/3 = 15
The average = (18 + 12 + 13 + 17) ÷ 4 = 60 ÷ 4 = 15
(12+14+16+18)/4 = 15
It is: (15+18)+12 = 45
The average is 75/5 = 15
(15*12+16*15+18*14)/4913.7142857 is the true average age
GCF(12, 15, 18) = 3
LCM of 12 and 15 and 18 is 180.
-12 + 18 - (-15) = -12 + 18 +15 = 21