Finding the Fourth Proportional to 1,085.63, 1,498.43 and 620.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.63 : 1,498.43 = 620.15 : x
2. Step 2: Convert to fraction form
   1,085.63/1,498.43 = 620.15/x
3. Step 3: Cross multiply
   1,085.63x = 1,498.43 × 620.15
4. Step 4: Simplify right side
   1,085.63x = 929,251.36
5. Step 5: Solve for x
   x = 929,251.36/1,085.63
6. Step 6: Final answer
   x = 855.96