Finding the Fourth Proportional to 1,434.78, 1,978.71 and 1,123.74

Step by Step Solution

1. Step 1: Write the proportion equation
   1,434.78 : 1,978.71 = 1,123.74 : x
2. Step 2: Convert to fraction form
   1,434.78/1,978.71 = 1,123.74/x
3. Step 3: Cross multiply
   1,434.78x = 1,978.71 × 1,123.74
4. Step 4: Simplify right side
   1,434.78x = 2,223,555.58
5. Step 5: Solve for x
   x = 2,223,555.58/1,434.78
6. Step 6: Final answer
   x = 1,549.75