Finding the Fourth Proportional to 1,139.96, 1,572.42 and 673.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.96 : 1,572.42 = 673.88 : x
2. Step 2: Convert to fraction form
   1,139.96/1,572.42 = 673.88/x
3. Step 3: Cross multiply
   1,139.96x = 1,572.42 × 673.88
4. Step 4: Simplify right side
   1,139.96x = 1,059,622.39
5. Step 5: Solve for x
   x = 1,059,622.39/1,139.96
6. Step 6: Final answer
   x = 929.53