Finding the Fourth Proportional to 1,041.18, 1,436.70 and 621.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,041.18 : 1,436.70 = 621.55 : x
2. Step 2: Convert to fraction form
   1,041.18/1,436.70 = 621.55/x
3. Step 3: Cross multiply
   1,041.18x = 1,436.70 × 621.55
4. Step 4: Simplify right side
   1,041.18x = 892,980.89
5. Step 5: Solve for x
   x = 892,980.89/1,041.18
6. Step 6: Final answer
   x = 857.66