Finding the Fourth Proportional to 1,111.59, 1,664.55 and 928.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.59 : 1,664.55 = 928.53 : x
2. Step 2: Convert to fraction form
   1,111.59/1,664.55 = 928.53/x
3. Step 3: Cross multiply
   1,111.59x = 1,664.55 × 928.53
4. Step 4: Simplify right side
   1,111.59x = 1,545,584.61
5. Step 5: Solve for x
   x = 1,545,584.61/1,111.59
6. Step 6: Final answer
   x = 1,390.43