Finding the Fourth Proportional to 123,215.32, 170,073.50 and 72,239.12

Step by Step Solution

1. Step 1: Write the proportion equation
   123,215.32 : 170,073.50 = 72,239.12 : x
2. Step 2: Convert to fraction form
   123,215.32/170,073.50 = 72,239.12/x
3. Step 3: Cross multiply
   123,215.32x = 170,073.50 × 72,239.12
4. Step 4: Simplify right side
   123,215.32x = 12,285,958,763.76
5. Step 5: Solve for x
   x = 12,285,958,763.76/123,215.32
6. Step 6: Final answer
   x = 99,711.29