Finding the Fourth Proportional to 1,085.90, 1,498.41 and 613.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,085.90 : 1,498.41 = 613.76 : x
2. Step 2: Convert to fraction form
   1,085.90/1,498.41 = 613.76/x
3. Step 3: Cross multiply
   1,085.90x = 1,498.41 × 613.76
4. Step 4: Simplify right side
   1,085.90x = 919,656.63
5. Step 5: Solve for x
   x = 919,656.63/1,085.90
6. Step 6: Final answer
   x = 846.91