Finding the Fourth Proportional to 30,860.80, 42,588.72 and 18,930.72

Step by Step Solution

1. Step 1: Write the proportion equation
   30,860.80 : 42,588.72 = 18,930.72 : x
2. Step 2: Convert to fraction form
   30,860.80/42,588.72 = 18,930.72/x
3. Step 3: Cross multiply
   30,860.80x = 42,588.72 × 18,930.72
4. Step 4: Simplify right side
   30,860.80x = 806,235,133.48
5. Step 5: Solve for x
   x = 806,235,133.48/30,860.80
6. Step 6: Final answer
   x = 26,124.89