Finding the Fourth Proportional to 1,128.58, 1,557.36 and 656.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,128.58 : 1,557.36 = 656.55 : x
2. Step 2: Convert to fraction form
   1,128.58/1,557.36 = 656.55/x
3. Step 3: Cross multiply
   1,128.58x = 1,557.36 × 656.55
4. Step 4: Simplify right side
   1,128.58x = 1,022,484.71
5. Step 5: Solve for x
   x = 1,022,484.71/1,128.58
6. Step 6: Final answer
   x = 905.99