Finding the Fourth Proportional to 1,107.89, 1,528.90 and 610.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,107.89 : 1,528.90 = 610.55 : x
2. Step 2: Convert to fraction form
   1,107.89/1,528.90 = 610.55/x
3. Step 3: Cross multiply
   1,107.89x = 1,528.90 × 610.55
4. Step 4: Simplify right side
   1,107.89x = 933,460.72
5. Step 5: Solve for x
   x = 933,460.72/1,107.89
6. Step 6: Final answer
   x = 842.56