Finding the Fourth Proportional to 1,139.10, 1,561.71 and 1,118.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.10 : 1,561.71 = 1,118.34 : x
2. Step 2: Convert to fraction form
   1,139.10/1,561.71 = 1,118.34/x
3. Step 3: Cross multiply
   1,139.10x = 1,561.71 × 1,118.34
4. Step 4: Simplify right side
   1,139.10x = 1,746,517.87
5. Step 5: Solve for x
   x = 1,746,517.87/1,139.10
6. Step 6: Final answer
   x = 1,533.24