Finding the Fourth Proportional to 1,054.89, 1,455.50 and 612.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,054.89 : 1,455.50 = 612.71 : x
2. Step 2: Convert to fraction form
   1,054.89/1,455.50 = 612.71/x
3. Step 3: Cross multiply
   1,054.89x = 1,455.50 × 612.71
4. Step 4: Simplify right side
   1,054.89x = 891,796.34
5. Step 5: Solve for x
   x = 891,796.34/1,054.89
6. Step 6: Final answer
   x = 845.40