Finding the Fourth Proportional to 2,620.02, 3,929.70 and 771.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,620.02 : 3,929.70 = 771.15 : x
2. Step 2: Convert to fraction form
   2,620.02/3,929.70 = 771.15/x
3. Step 3: Cross multiply
   2,620.02x = 3,929.70 × 771.15
4. Step 4: Simplify right side
   2,620.02x = 3,030,388.16
5. Step 5: Solve for x
   x = 3,030,388.16/2,620.02
6. Step 6: Final answer
   x = 1,156.63