Finding the Fourth Proportional to 21,404.32, 29,531.28 and 13,017.76

Step by Step Solution

1. Step 1: Write the proportion equation
   21,404.32 : 29,531.28 = 13,017.76 : x
2. Step 2: Convert to fraction form
   21,404.32/29,531.28 = 13,017.76/x
3. Step 3: Cross multiply
   21,404.32x = 29,531.28 × 13,017.76
4. Step 4: Simplify right side
   21,404.32x = 384,431,115.53
5. Step 5: Solve for x
   x = 384,431,115.53/21,404.32
6. Step 6: Final answer
   x = 17,960.45