Alana is 4 years older than her brother Ernie. Ernie is 2 years older than their sister Amelia. Amelia is 10 years younger than their brother Mazo. If Mazo is 17 years old, how old is Alana?

if mazo is 17, and amelia is 10 years younger, than she is 7. (17-10=7) if ernie is 2 years older than amelia, than ernie is 9. (7+2=9) if alana is 4 years older than ernie, alana is 13. (4+9=13)