Finding the Fourth Proportional to 2,438.40, 3,658.76 and 978.56

Step by Step Solution

1. Step 1: Write the proportion equation
   2,438.40 : 3,658.76 = 978.56 : x
2. Step 2: Convert to fraction form
   2,438.40/3,658.76 = 978.56/x
3. Step 3: Cross multiply
   2,438.40x = 3,658.76 × 978.56
4. Step 4: Simplify right side
   2,438.40x = 3,580,316.19
5. Step 5: Solve for x
   x = 3,580,316.19/2,438.40
6. Step 6: Final answer
   x = 1,468.31