Finding the Fourth Proportional to 12,826.21, 17,707.53 and 9,777.39

Step by Step Solution

1. Step 1: Write the proportion equation
   12,826.21 : 17,707.53 = 9,777.39 : x
2. Step 2: Convert to fraction form
   12,826.21/17,707.53 = 9,777.39/x
3. Step 3: Cross multiply
   12,826.21x = 17,707.53 × 9,777.39
4. Step 4: Simplify right side
   12,826.21x = 173,133,377.86
5. Step 5: Solve for x
   x = 173,133,377.86/12,826.21
6. Step 6: Final answer
   x = 13,498.41