Finding the Fourth Proportional to 42,631.72, 63,921.82 and 16,990

Step by Step Solution

1. Step 1: Write the proportion equation
   42,631.72 : 63,921.82 = 16,990 : x
2. Step 2: Convert to fraction form
   42,631.72/63,921.82 = 16,990/x
3. Step 3: Cross multiply
   42,631.72x = 63,921.82 × 16,990
4. Step 4: Simplify right side
   42,631.72x = 1,086,031,721.80
5. Step 5: Solve for x
   x = 1,086,031,721.80/42,631.72
6. Step 6: Final answer
   x = 25,474.73