Finding the Fourth Proportional to 2,621.57, 3,933.77 and 978.39

Step by Step Solution

1. Step 1: Write the proportion equation
   2,621.57 : 3,933.77 = 978.39 : x
2. Step 2: Convert to fraction form
   2,621.57/3,933.77 = 978.39/x
3. Step 3: Cross multiply
   2,621.57x = 3,933.77 × 978.39
4. Step 4: Simplify right side
   2,621.57x = 3,848,756.34
5. Step 5: Solve for x
   x = 3,848,756.34/2,621.57
6. Step 6: Final answer
   x = 1,468.11