Finding the Fourth Proportional to 21,071.16, 29,068.34 and 13,513.86

Step by Step Solution

1. Step 1: Write the proportion equation
   21,071.16 : 29,068.34 = 13,513.86 : x
2. Step 2: Convert to fraction form
   21,071.16/29,068.34 = 13,513.86/x
3. Step 3: Cross multiply
   21,071.16x = 29,068.34 × 13,513.86
4. Step 4: Simplify right side
   21,071.16x = 392,825,409.62
5. Step 5: Solve for x
   x = 392,825,409.62/21,071.16
6. Step 6: Final answer
   x = 18,642.80