Finding the Fourth Proportional to 12,789.21, 17,657.81 and 8,011.13

Step by Step Solution

1. Step 1: Write the proportion equation
   12,789.21 : 17,657.81 = 8,011.13 : x
2. Step 2: Convert to fraction form
   12,789.21/17,657.81 = 8,011.13/x
3. Step 3: Cross multiply
   12,789.21x = 17,657.81 × 8,011.13
4. Step 4: Simplify right side
   12,789.21x = 141,459,011.43
5. Step 5: Solve for x
   x = 141,459,011.43/12,789.21
6. Step 6: Final answer
   x = 11,060.81