Finding the Fourth Proportional to 2,538.90, 3,806.55 and 978.30

Step by Step Solution

1. Step 1: Write the proportion equation
   2,538.90 : 3,806.55 = 978.30 : x
2. Step 2: Convert to fraction form
   2,538.90/3,806.55 = 978.30/x
3. Step 3: Cross multiply
   2,538.90x = 3,806.55 × 978.30
4. Step 4: Simplify right side
   2,538.90x = 3,723,947.87
5. Step 5: Solve for x
   x = 3,723,947.87/2,538.90
6. Step 6: Final answer
   x = 1,466.76