Sum of age of 7 children born at interval of 7 years is 238. What is the age of youngest child?

Answer 1

x+(x+7)+(x+14)+(x+21)+(x+28)+(x+35)+(x+42)=238
7x+147=238
7x=238-147
7x=91
x=91/7
x=13
13+20+27+34+41+48+55=238
Answer is 13