Finding the Fourth Proportional to 1,388.32, 2,076.72 and 1,042.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.32 : 2,076.72 = 1,042.72 : x
2. Step 2: Convert to fraction form
   1,388.32/2,076.72 = 1,042.72/x
3. Step 3: Cross multiply
   1,388.32x = 2,076.72 × 1,042.72
4. Step 4: Simplify right side
   1,388.32x = 2,165,437.48
5. Step 5: Solve for x
   x = 2,165,437.48/1,388.32
6. Step 6: Final answer
   x = 1,559.75