Finding the Fourth Proportional to 31,106.58, 42,950.61 and 20,511.06

Step by Step Solution

1. Step 1: Write the proportion equation
   31,106.58 : 42,950.61 = 20,511.06 : x
2. Step 2: Convert to fraction form
   31,106.58/42,950.61 = 20,511.06/x
3. Step 3: Cross multiply
   31,106.58x = 42,950.61 × 20,511.06
4. Step 4: Simplify right side
   31,106.58x = 880,962,538.75
5. Step 5: Solve for x
   x = 880,962,538.75/31,106.58
6. Step 6: Final answer
   x = 28,320.78