Finding the Fourth Proportional to 2,072.30, 3,108.47 and 612.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.30 : 3,108.47 = 612.50 : x
2. Step 2: Convert to fraction form
   2,072.30/3,108.47 = 612.50/x
3. Step 3: Cross multiply
   2,072.30x = 3,108.47 × 612.50
4. Step 4: Simplify right side
   2,072.30x = 1,903,919.27
5. Step 5: Solve for x
   x = 1,903,919.27/2,072.30
6. Step 6: Final answer
   x = 918.75