Finding the Fourth Proportional to 12,913.31, 17,826.27 and 9,928.10

Step by Step Solution

1. Step 1: Write the proportion equation
   12,913.31 : 17,826.27 = 9,928.10 : x
2. Step 2: Convert to fraction form
   12,913.31/17,826.27 = 9,928.10/x
3. Step 3: Cross multiply
   12,913.31x = 17,826.27 × 9,928.10
4. Step 4: Simplify right side
   12,913.31x = 176,980,991.19
5. Step 5: Solve for x
   x = 176,980,991.19/12,913.31
6. Step 6: Final answer
   x = 13,705.32