Finding the Fourth Proportional to 1,641.28, 2,264.77 and 978.04

Step by Step Solution

1. Step 1: Write the proportion equation
   1,641.28 : 2,264.77 = 978.04 : x
2. Step 2: Convert to fraction form
   1,641.28/2,264.77 = 978.04/x
3. Step 3: Cross multiply
   1,641.28x = 2,264.77 × 978.04
4. Step 4: Simplify right side
   1,641.28x = 2,215,035.65
5. Step 5: Solve for x
   x = 2,215,035.65/1,641.28
6. Step 6: Final answer
   x = 1,349.58