Finding the Fourth Proportional to 72,145.32, 99,508.88 and 50,639.88

Step by Step Solution

1. Step 1: Write the proportion equation
   72,145.32 : 99,508.88 = 50,639.88 : x
2. Step 2: Convert to fraction form
   72,145.32/99,508.88 = 50,639.88/x
3. Step 3: Cross multiply
   72,145.32x = 99,508.88 × 50,639.88
4. Step 4: Simplify right side
   72,145.32x = 5,039,117,742.13
5. Step 5: Solve for x
   x = 5,039,117,742.13/72,145.32
6. Step 6: Final answer
   x = 69,846.77