Finding the Fourth Proportional to 1,085.56, 1,498.06 and 619.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.56 : 1,498.06 = 619.80 : x
2. Step 2: Convert to fraction form
   1,085.56/1,498.06 = 619.80/x
3. Step 3: Cross multiply
   1,085.56x = 1,498.06 × 619.80
4. Step 4: Simplify right side
   1,085.56x = 928,497.59
5. Step 5: Solve for x
   x = 928,497.59/1,085.56
6. Step 6: Final answer
   x = 855.32