Finding the Fourth Proportional to 72,690.72, 108,991.42 and 28,265.68

Step by Step Solution

1. Step 1: Write the proportion equation
   72,690.72 : 108,991.42 = 28,265.68 : x
2. Step 2: Convert to fraction form
   72,690.72/108,991.42 = 28,265.68/x
3. Step 3: Cross multiply
   72,690.72x = 108,991.42 × 28,265.68
4. Step 4: Simplify right side
   72,690.72x = 3,080,716,600.47
5. Step 5: Solve for x
   x = 3,080,716,600.47/72,690.72
6. Step 6: Final answer
   x = 42,381.15