Finding the Fourth Proportional to 1,688.85, 2,532.06 and 1,139.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,688.85 : 2,532.06 = 1,139.67 : x
2. Step 2: Convert to fraction form
   1,688.85/2,532.06 = 1,139.67/x
3. Step 3: Cross multiply
   1,688.85x = 2,532.06 × 1,139.67
4. Step 4: Simplify right side
   1,688.85x = 2,885,712.82
5. Step 5: Solve for x
   x = 2,885,712.82/1,688.85
6. Step 6: Final answer
   x = 1,708.69