Final answer:
Ronnie collected $158 after solving a system of equations based on the information provided about the money raised by each group member.
Step-by-step explanation:
Let's denote the amount of money Mike raised as M. According to the problem, Ronnie raised M + $30. Bobby raised $12 less than Ronnie, which is (M + $30) - $12 or M + $18. The total amount they collected is $432, so we can write the equation M + (M + $30) + (M + $18) = $432. Combining like terms, we have 3M + $48 = $432. Subtracting $48 from both sides gives us 3M = $384. Dividing both sides by 3 gives us M = $128. Now we can find out how much Ronnie collected by adding $30 to Mike's amount: M + $30 = $128 + $30 = $158. Hence, Ronnie collected $158.