Finding the Fourth Proportional to 2,088.72, 3,131.13 and 771.74

Step by Step Solution

1. Step 1: Write the proportion equation
   2,088.72 : 3,131.13 = 771.74 : x
2. Step 2: Convert to fraction form
   2,088.72/3,131.13 = 771.74/x
3. Step 3: Cross multiply
   2,088.72x = 3,131.13 × 771.74
4. Step 4: Simplify right side
   2,088.72x = 2,416,418.27
5. Step 5: Solve for x
   x = 2,416,418.27/2,088.72
6. Step 6: Final answer
   x = 1,156.89