Answer:
$17.20
Step-by-step explanation:
To easily get the ratio figured out between Paul, Colin and Brian, try seeing how much the ratio adds up to. With 2:3:4, there is a total of 9; so take 1/9th of 77.40 to get $8.60
You can convert these ratios to fractions, with Paul getting 2/9ths, Colin getting 3/9ths and Brian getting 4/9ths
As Brian is effectively getting double the amount of money, you can just take the amount Paul is getting in tips and use that as the reference for how much Brian is earning which is $8.60 x 2 or in this case, $17.20