Finding the Fourth Proportional to 30,756.48, 42,450.84 and 20,139.93

Step by Step Solution

1. Step 1: Write the proportion equation
   30,756.48 : 42,450.84 = 20,139.93 : x
2. Step 2: Convert to fraction form
   30,756.48/42,450.84 = 20,139.93/x
3. Step 3: Cross multiply
   30,756.48x = 42,450.84 × 20,139.93
4. Step 4: Simplify right side
   30,756.48x = 854,956,946.04
5. Step 5: Solve for x
   x = 854,956,946.04/30,756.48
6. Step 6: Final answer
   x = 27,797.62