Idon't know how to solve both questions 5 and 6. can anyone me?

Question 5
fee for 10 = 10 × 429
fee for 10 = 4,290

Every 11 person, the pupils only pay 4,290. There are 44 pupils.
fee for 44 = 44/11 × 4,290
fee for 44 = 4 × 4,290
fee for 44 = 13,160

They pay $13,160

Question 6
The nearest multiplication of 50 is 150
from father = 150/50 × 20
from father = 3 × 20
from father = 60

Sally's father gives $60