Finding the Fourth Proportional to 1,128.55, 1,558.13 and 709.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,128.55 : 1,558.13 = 709.48 : x
2. Step 2: Convert to fraction form
   1,128.55/1,558.13 = 709.48/x
3. Step 3: Cross multiply
   1,128.55x = 1,558.13 × 709.48
4. Step 4: Simplify right side
   1,128.55x = 1,105,462.07
5. Step 5: Solve for x
   x = 1,105,462.07/1,128.55
6. Step 6: Final answer
   x = 979.54