Finding the Fourth Proportional to 2,709.76, 4,066.40 and 978.24

Step by Step Solution

1. Step 1: Write the proportion equation
   2,709.76 : 4,066.40 = 978.24 : x
2. Step 2: Convert to fraction form
   2,709.76/4,066.40 = 978.24/x
3. Step 3: Cross multiply
   2,709.76x = 4,066.40 × 978.24
4. Step 4: Simplify right side
   2,709.76x = 3,977,915.14
5. Step 5: Solve for x
   x = 3,977,915.14/2,709.76
6. Step 6: Final answer
   x = 1,468.00