A factor of 20 but not a multiple of 5 would probably be 4
Step-by-step explanation:
28 + 19 + 13 equal 60%
therefore 40% divided by 60% multiply by 160 gives number of chicks
4n/4n-4 × n-1/n+1
= 4n(n-1)/(4n-4)(n+1)
= (4n^2 - 4n)/(4n^2 + 4n - 4n-4)
= (4n^2 - 4n)/(4n^2 - 4)
= 4(n^2 - n)/4(n^2 - 1)
=(n^2 - n)/(n^2 - 1)
