Finding the Fourth Proportional to 1,925.78, 2,657.61 and 1,139.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,925.78 : 2,657.61 = 1,139.67 : x
2. Step 2: Convert to fraction form
   1,925.78/2,657.61 = 1,139.67/x
3. Step 3: Cross multiply
   1,925.78x = 2,657.61 × 1,139.67
4. Step 4: Simplify right side
   1,925.78x = 3,028,798.39
5. Step 5: Solve for x
   x = 3,028,798.39/1,925.78
6. Step 6: Final answer
   x = 1,572.77