Finding the Fourth Proportional to 30,930.58, 42,719.17 and 20,841.50

Step by Step Solution

1. Step 1: Write the proportion equation
   30,930.58 : 42,719.17 = 20,841.50 : x
2. Step 2: Convert to fraction form
   30,930.58/42,719.17 = 20,841.50/x
3. Step 3: Cross multiply
   30,930.58x = 42,719.17 × 20,841.50
4. Step 4: Simplify right side
   30,930.58x = 890,331,636.25
5. Step 5: Solve for x
   x = 890,331,636.25/30,930.58
6. Step 6: Final answer
   x = 28,784.84