Finding the Fourth Proportional to 21,602.61, 29,812.73 and 12,172.05

Step by Step Solution

1. Step 1: Write the proportion equation
   21,602.61 : 29,812.73 = 12,172.05 : x
2. Step 2: Convert to fraction form
   21,602.61/29,812.73 = 12,172.05/x
3. Step 3: Cross multiply
   21,602.61x = 29,812.73 × 12,172.05
4. Step 4: Simplify right side
   21,602.61x = 362,881,979.34
5. Step 5: Solve for x
   x = 362,881,979.34/21,602.61
6. Step 6: Final answer
   x = 16,798.06