Finding the Fourth Proportional to 21,053.42, 31,577.55 and 13,156.63

Step by Step Solution

1. Step 1: Write the proportion equation
   21,053.42 : 31,577.55 = 13,156.63 : x
2. Step 2: Convert to fraction form
   21,053.42/31,577.55 = 13,156.63/x
3. Step 3: Cross multiply
   21,053.42x = 31,577.55 × 13,156.63
4. Step 4: Simplify right side
   21,053.42x = 415,454,013.38
5. Step 5: Solve for x
   x = 415,454,013.38/21,053.42
6. Step 6: Final answer
   x = 19,733.33