Finding the Fourth Proportional to 13,315.32, 19,978.78 and 7,152.12

Step by Step Solution

1. Step 1: Write the proportion equation
   13,315.32 : 19,978.78 = 7,152.12 : x
2. Step 2: Convert to fraction form
   13,315.32/19,978.78 = 7,152.12/x
3. Step 3: Cross multiply
   13,315.32x = 19,978.78 × 7,152.12
4. Step 4: Simplify right side
   13,315.32x = 142,890,632.01
5. Step 5: Solve for x
   x = 142,890,632.01/13,315.32
6. Step 6: Final answer
   x = 10,731.30