MERRY CHRISTMASS: pls help me or i will cry ngl

Pelle's sister is three years older than pelle the father is 5 times as old as pelle the mother was 28 when the sister was born altogether they are 98 years old how old is pelle?

F(n + 1) = f(n) – 8. if f(1) = 100, what is f(6)?

If you have the following equation, 2/3x+5/6-x=2-3/4x what would you multiply each term by to get rid of all the fractions