Finding the Fourth Proportional to 51,911.61, 71,638.69 and 30,690.69

Step by Step Solution

1. Step 1: Write the proportion equation
   51,911.61 : 71,638.69 = 30,690.69 : x
2. Step 2: Convert to fraction form
   51,911.61/71,638.69 = 30,690.69/x
3. Step 3: Cross multiply
   51,911.61x = 71,638.69 × 30,690.69
4. Step 4: Simplify right side
   51,911.61x = 2,198,641,082.62
5. Step 5: Solve for x
   x = 2,198,641,082.62/51,911.61
6. Step 6: Final answer
   x = 42,353.55