Finding the Fourth Proportional to 12,612.79, 18,917.61 and 5,216.32

Step by Step Solution

1. Step 1: Write the proportion equation
   12,612.79 : 18,917.61 = 5,216.32 : x
2. Step 2: Convert to fraction form
   12,612.79/18,917.61 = 5,216.32/x
3. Step 3: Cross multiply
   12,612.79x = 18,917.61 × 5,216.32
4. Step 4: Simplify right side
   12,612.79x = 98,680,307.40
5. Step 5: Solve for x
   x = 98,680,307.40/12,612.79
6. Step 6: Final answer
   x = 7,823.83