Finding the Fourth Proportional to 12,890.68, 17,787.57 and 7,224.12

Step by Step Solution

1. Step 1: Write the proportion equation
   12,890.68 : 17,787.57 = 7,224.12 : x
2. Step 2: Convert to fraction form
   12,890.68/17,787.57 = 7,224.12/x
3. Step 3: Cross multiply
   12,890.68x = 17,787.57 × 7,224.12
4. Step 4: Simplify right side
   12,890.68x = 128,499,513.10
5. Step 5: Solve for x
   x = 128,499,513.10/12,890.68
6. Step 6: Final answer
   x = 9,968.41