Finding the Fourth Proportional to 1,139.23, 1,709.34 and 591.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.23 : 1,709.34 = 591.81 : x
2. Step 2: Convert to fraction form
   1,139.23/1,709.34 = 591.81/x
3. Step 3: Cross multiply
   1,139.23x = 1,709.34 × 591.81
4. Step 4: Simplify right side
   1,139.23x = 1,011,604.51
5. Step 5: Solve for x
   x = 1,011,604.51/1,139.23
6. Step 6: Final answer
   x = 887.97