Answer:
14
Step-by-step explanation:
first you add them all up and then divide alll of them again
you add them all up and divide by how much there are
(10+11+12+13+14+15+16+17+18)=126
(126/9)=14
10/15 & 6/15
6x3x2
XY - X + 2Y -2 =X(Y-1) + 2(Y-1) = 2X(Y-1)
2,1
