Finding the Fourth Proportional to 21,510.28, 29,684.37 and 12,079.72

Step by Step Solution

1. Step 1: Write the proportion equation
   21,510.28 : 29,684.37 = 12,079.72 : x
2. Step 2: Convert to fraction form
   21,510.28/29,684.37 = 12,079.72/x
3. Step 3: Cross multiply
   21,510.28x = 29,684.37 × 12,079.72
4. Step 4: Simplify right side
   21,510.28x = 358,578,877.98
5. Step 5: Solve for x
   x = 358,578,877.98/21,510.28
6. Step 6: Final answer
   x = 16,670.12