we assume that jamie is a boy or whatever
his sibbling is sibbling x
together, ages are 35
either jamie is 4 times sibbling x or sibbling x is 4 times jamie
anyway
lets say jamie=y and sibbling x=x
if we solve for jamie is 4 times as old as x then we can switch them if we are wrong
jamie is 4 times sibbling x age
x=4y
together it is 35
x+y=35
sub 4y for x
4y+y=35
5y=35
divide both sides by 5
y=7
sub back
x=4y
x=4(7)
x=28
either it is
jamie is 28 and sibbling is 7 or
sibbling is 28 and jamie is 7
depends but you didn't say who is older and who is 4 times of who