Finding the Fourth Proportional to 1,139.37, 1,573.38 and 1,077.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.37 : 1,573.38 = 1,077.99 : x
2. Step 2: Convert to fraction form
   1,139.37/1,573.38 = 1,077.99/x
3. Step 3: Cross multiply
   1,139.37x = 1,573.38 × 1,077.99
4. Step 4: Simplify right side
   1,139.37x = 1,696,087.91
5. Step 5: Solve for x
   x = 1,696,087.91/1,139.37
6. Step 6: Final answer
   x = 1,488.62