Finding the Fourth Proportional to 1,081.34, 1,621.30 and 612.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,081.34 : 1,621.30 = 612.82 : x
2. Step 2: Convert to fraction form
   1,081.34/1,621.30 = 612.82/x
3. Step 3: Cross multiply
   1,081.34x = 1,621.30 × 612.82
4. Step 4: Simplify right side
   1,081.34x = 993,565.07
5. Step 5: Solve for x
   x = 993,565.07/1,081.34
6. Step 6: Final answer
   x = 918.83