Finding the Fourth Proportional to 1,112.72, 1,530.98 and 1,085.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,112.72 : 1,530.98 = 1,085.39 : x
2. Step 2: Convert to fraction form
   1,112.72/1,530.98 = 1,085.39/x
3. Step 3: Cross multiply
   1,112.72x = 1,530.98 × 1,085.39
4. Step 4: Simplify right side
   1,112.72x = 1,661,697.30
5. Step 5: Solve for x
   x = 1,661,697.30/1,112.72
6. Step 6: Final answer
   x = 1,493.37