Finding the Fourth Proportional to 2,612.40, 3,920.16 and 1,152.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,612.40 : 3,920.16 = 1,152.72 : x
2. Step 2: Convert to fraction form
   2,612.40/3,920.16 = 1,152.72/x
3. Step 3: Cross multiply
   2,612.40x = 3,920.16 × 1,152.72
4. Step 4: Simplify right side
   2,612.40x = 4,518,846.84
5. Step 5: Solve for x
   x = 4,518,846.84/2,612.40
6. Step 6: Final answer
   x = 1,729.77