Finding the Fourth Proportional to 12,420.84, 17,148.06 and 7,707.72

Step by Step Solution

1. Step 1: Write the proportion equation
   12,420.84 : 17,148.06 = 7,707.72 : x
2. Step 2: Convert to fraction form
   12,420.84/17,148.06 = 7,707.72/x
3. Step 3: Cross multiply
   12,420.84x = 17,148.06 × 7,707.72
4. Step 4: Simplify right side
   12,420.84x = 132,172,445.02
5. Step 5: Solve for x
   x = 132,172,445.02/12,420.84
6. Step 6: Final answer
   x = 10,641.18