Finding the Fourth Proportional to 1,040.48, 1,436.17 and 621.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,040.48 : 1,436.17 = 621.12 : x
2. Step 2: Convert to fraction form
   1,040.48/1,436.17 = 621.12/x
3. Step 3: Cross multiply
   1,040.48x = 1,436.17 × 621.12
4. Step 4: Simplify right side
   1,040.48x = 892,030.80
5. Step 5: Solve for x
   x = 892,030.80/1,040.48
6. Step 6: Final answer
   x = 857.33