Finding the Fourth Proportional to 2,072.88, 3,109.46 and 612.45

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.88 : 3,109.46 = 612.45 : x
2. Step 2: Convert to fraction form
   2,072.88/3,109.46 = 612.45/x
3. Step 3: Cross multiply
   2,072.88x = 3,109.46 × 612.45
4. Step 4: Simplify right side
   2,072.88x = 1,904,385.71
5. Step 5: Solve for x
   x = 1,904,385.71/2,072.88
6. Step 6: Final answer
   x = 918.71