Finding the Fourth Proportional to 2,072.16, 3,108.24 and 978.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,072.16 : 3,108.24 = 978.72 : x
2. Step 2: Convert to fraction form
   2,072.16/3,108.24 = 978.72/x
3. Step 3: Cross multiply
   2,072.16x = 3,108.24 × 978.72
4. Step 4: Simplify right side
   2,072.16x = 3,042,096.65
5. Step 5: Solve for x
   x = 3,042,096.65/2,072.16
6. Step 6: Final answer
   x = 1,468.08