Finding the Fourth Proportional to 21,939.72, 30,264.51 and 13,445.96

Step by Step Solution

1. Step 1: Write the proportion equation
   21,939.72 : 30,264.51 = 13,445.96 : x
2. Step 2: Convert to fraction form
   21,939.72/30,264.51 = 13,445.96/x
3. Step 3: Cross multiply
   21,939.72x = 30,264.51 × 13,445.96
4. Step 4: Simplify right side
   21,939.72x = 406,935,315.22
5. Step 5: Solve for x
   x = 406,935,315.22/21,939.72
6. Step 6: Final answer
   x = 18,547.88