Finding the Fourth Proportional to 1,100.78, 1,519.46 and 681.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,100.78 : 1,519.46 = 681.45 : x
2. Step 2: Convert to fraction form
   1,100.78/1,519.46 = 681.45/x
3. Step 3: Cross multiply
   1,100.78x = 1,519.46 × 681.45
4. Step 4: Simplify right side
   1,100.78x = 1,035,432.61
5. Step 5: Solve for x
   x = 1,035,432.61/1,100.78
6. Step 6: Final answer
   x = 940.64