Finding the Fourth Proportional to 1,856.34, 2,784.78 and 557.91

Step by Step Solution

1. Step 1: Write the proportion equation
   1,856.34 : 2,784.78 = 557.91 : x
2. Step 2: Convert to fraction form
   1,856.34/2,784.78 = 557.91/x
3. Step 3: Cross multiply
   1,856.34x = 2,784.78 × 557.91
4. Step 4: Simplify right side
   1,856.34x = 1,553,656.61
5. Step 5: Solve for x
   x = 1,553,656.61/1,856.34
6. Step 6: Final answer
   x = 836.95