Finding the Fourth Proportional to 12,781.89, 17,638.87 and 7,116.52

Step by Step Solution

1. Step 1: Write the proportion equation
   12,781.89 : 17,638.87 = 7,116.52 : x
2. Step 2: Convert to fraction form
   12,781.89/17,638.87 = 7,116.52/x
3. Step 3: Cross multiply
   12,781.89x = 17,638.87 × 7,116.52
4. Step 4: Simplify right side
   12,781.89x = 125,527,327.04
5. Step 5: Solve for x
   x = 125,527,327.04/12,781.89
6. Step 6: Final answer
   x = 9,820.72