Finding the Fourth Proportional to 2,622.35, 3,934.20 and 978.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,622.35 : 3,934.20 = 978.91 : x
2. Step 2: Convert to fraction form
   2,622.35/3,934.20 = 978.91/x
3. Step 3: Cross multiply
   2,622.35x = 3,934.20 × 978.91
4. Step 4: Simplify right side
   2,622.35x = 3,851,227.72
5. Step 5: Solve for x
   x = 3,851,227.72/2,622.35
6. Step 6: Final answer
   x = 1,468.62