Finding the Fourth Proportional to 13,215, 19,785.60 and 10,902.84

Step by Step Solution

1. Step 1: Write the proportion equation
   13,215 : 19,785.60 = 10,902.84 : x
2. Step 2: Convert to fraction form
   13,215/19,785.60 = 10,902.84/x
3. Step 3: Cross multiply
   13,215x = 19,785.60 × 10,902.84
4. Step 4: Simplify right side
   13,215x = 215,719,231.10
5. Step 5: Solve for x
   x = 215,719,231.10/13,215
6. Step 6: Final answer
   x = 16,323.82