Question 1008655
$30 + $20 + $10 = $60.

The person that invested the smallest amount, in this case, Brian gets the $200.

  Simple thing to do is know how much percentage of the total investment Brian contributed.

B% of 60 = 10
Mathematically,
 60B/100 = 10
60B = 1000
B =100/6


Therefore, We ask, if 100/6 percent could yield $200. How much was the total payout?

100/6% of X = 200
Mathematically,
100X/600 = 200
100X = 120000
X = $1,200
   The total amount they won is $1,200.
Am kinda in a hurry, so i didn't simplify much. Hope you get it.

(Engr. Terry, Nigeria)