Finding the Fourth Proportional to 12,402.51, 17,111.16 and 7,928.88

Step by Step Solution

1. Step 1: Write the proportion equation
   12,402.51 : 17,111.16 = 7,928.88 : x
2. Step 2: Convert to fraction form
   12,402.51/17,111.16 = 7,928.88/x
3. Step 3: Cross multiply
   12,402.51x = 17,111.16 × 7,928.88
4. Step 4: Simplify right side
   12,402.51x = 135,672,334.30
5. Step 5: Solve for x
   x = 135,672,334.30/12,402.51
6. Step 6: Final answer
   x = 10,939.10