Finding the Fourth Proportional to 21,672.78, 32,482.56 and 12,320.64

Step by Step Solution

1. Step 1: Write the proportion equation
   21,672.78 : 32,482.56 = 12,320.64 : x
2. Step 2: Convert to fraction form
   21,672.78/32,482.56 = 12,320.64/x
3. Step 3: Cross multiply
   21,672.78x = 32,482.56 × 12,320.64
4. Step 4: Simplify right side
   21,672.78x = 400,205,928.04
5. Step 5: Solve for x
   x = 400,205,928.04/21,672.78
6. Step 6: Final answer
   x = 18,465.83