Finding the Fourth Proportional to 42,890.98, 64,338.52 and 20,723

Step by Step Solution

1. Step 1: Write the proportion equation
   42,890.98 : 64,338.52 = 20,723 : x
2. Step 2: Convert to fraction form
   42,890.98/64,338.52 = 20,723/x
3. Step 3: Cross multiply
   42,890.98x = 64,338.52 × 20,723
4. Step 4: Simplify right side
   42,890.98x = 1,333,287,149.96
5. Step 5: Solve for x
   x = 1,333,287,149.96/42,890.98
6. Step 6: Final answer
   x = 31,085.49