Finding the Fourth Proportional to 1,123,405.68, 1,549,921.32 and 639,628.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,123,405.68 : 1,549,921.32 = 639,628.59 : x
2. Step 2: Convert to fraction form
   1,123,405.68/1,549,921.32 = 639,628.59/x
3. Step 3: Cross multiply
   1,123,405.68x = 1,549,921.32 × 639,628.59
4. Step 4: Simplify right side
   1,123,405.68x = 991,373,988,522.54
5. Step 5: Solve for x
   x = 991,373,988,522.54/1,123,405.68
6. Step 6: Final answer
   x = 882,471.94