Question

Sean has a collection of less than 50 books. He counts his books in fours and has one left over He counts his books in fives and has three left over
How many books could Sean have? ​

Answer 1

Sean is less that 50 books

If you divide the number by 4 you get 1 left over

If you divide by 5 you get 3 left over

So the number can’t be a multiply of 4 or 5

I will write as a equation

S < 50
S / 4 = x.1
S / 5 = x.3

Hope this helps