Finding the Fourth Proportional to 1,911.78, 2,638.22 and 1,072.43

Step by Step Solution

1. Step 1: Write the proportion equation
   1,911.78 : 2,638.22 = 1,072.43 : x
2. Step 2: Convert to fraction form
   1,911.78/2,638.22 = 1,072.43/x
3. Step 3: Cross multiply
   1,911.78x = 2,638.22 × 1,072.43
4. Step 4: Simplify right side
   1,911.78x = 2,829,287.72
5. Step 5: Solve for x
   x = 2,829,287.72/1,911.78
6. Step 6: Final answer
   x = 1,479.92