Finding the Fourth Proportional to 1,055.72, 1,456.90 and 613.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,055.72 : 1,456.90 = 613.89 : x
2. Step 2: Convert to fraction form
   1,055.72/1,456.90 = 613.89/x
3. Step 3: Cross multiply
   1,055.72x = 1,456.90 × 613.89
4. Step 4: Simplify right side
   1,055.72x = 894,376.34
5. Step 5: Solve for x
   x = 894,376.34/1,055.72
6. Step 6: Final answer
   x = 847.17