Finding the Fourth Proportional to 1,641.32, 2,264.67 and 978.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,641.32 : 2,264.67 = 978.39 : x
2. Step 2: Convert to fraction form
   1,641.32/2,264.67 = 978.39/x
3. Step 3: Cross multiply
   1,641.32x = 2,264.67 × 978.39
4. Step 4: Simplify right side
   1,641.32x = 2,215,730.48
5. Step 5: Solve for x
   x = 2,215,730.48/1,641.32
6. Step 6: Final answer
   x = 1,349.97