Finding the Fourth Proportional to 1,912.86, 2,639.78 and 1,073.61

Step by Step Solution

1. Step 1: Write the proportion equation
   1,912.86 : 2,639.78 = 1,073.61 : x
2. Step 2: Convert to fraction form
   1,912.86/2,639.78 = 1,073.61/x
3. Step 3: Cross multiply
   1,912.86x = 2,639.78 × 1,073.61
4. Step 4: Simplify right side
   1,912.86x = 2,834,094.21
5. Step 5: Solve for x
   x = 2,834,094.21/1,912.86
6. Step 6: Final answer
   x = 1,481.60