Question 132371
Let take n=number of children
    h= sum of the ages of mother and children
then

(38+h)/(n+2) = 18
h/n+1 = 14
then
h=14(n+1)
then
38+14(n+1)=18(n+2)
then

38+14+14n=18n+36
-4n=-16
then
n=4

R: there are 4 children in the family