Finding the Fourth Proportional to 1,139.48, 1,705.69 and 618.19

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.48 : 1,705.69 = 618.19 : x
2. Step 2: Convert to fraction form
   1,139.48/1,705.69 = 618.19/x
3. Step 3: Cross multiply
   1,139.48x = 1,705.69 × 618.19
4. Step 4: Simplify right side
   1,139.48x = 1,054,440.50
5. Step 5: Solve for x
   x = 1,054,440.50/1,139.48
6. Step 6: Final answer
   x = 925.37