Finding the Fourth Proportional to 1,131.86, 1,696.70 and 618.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.86 : 1,696.70 = 618.50 : x
2. Step 2: Convert to fraction form
   1,131.86/1,696.70 = 618.50/x
3. Step 3: Cross multiply
   1,131.86x = 1,696.70 × 618.50
4. Step 4: Simplify right side
   1,131.86x = 1,049,408.95
5. Step 5: Solve for x
   x = 1,049,408.95/1,131.86
6. Step 6: Final answer
   x = 927.15