Constant: 4 i think because you can divide 20 by 4 to get 5 and 24 by 4 to get 6. So then probably the equation: is y=4x BUT DON'T PAY ATTENTION TO ME I GOT A B+ IN MATH:)
explanation: let's take 20 and 5 for example, if you divide 20 by 5, you will 4 of course. that's the proportionality for the first one. if you continue to divide x value by y value you will get 4. for the last two you would divide 28 by 4 and multiply 8 by 4.
