Finding the Fourth Proportional to 21,667.58, 29,902.65 and 12,711.81

Step by Step Solution

1. Step 1: Write the proportion equation
   21,667.58 : 29,902.65 = 12,711.81 : x
2. Step 2: Convert to fraction form
   21,667.58/29,902.65 = 12,711.81/x
3. Step 3: Cross multiply
   21,667.58x = 29,902.65 × 12,711.81
4. Step 4: Simplify right side
   21,667.58x = 380,116,805.30
5. Step 5: Solve for x
   x = 380,116,805.30/21,667.58
6. Step 6: Final answer
   x = 17,543.11