Finding the Fourth Proportional to 1,671.31, 2,507.39 and 978.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,671.31 : 2,507.39 = 978.56 : x
2. Step 2: Convert to fraction form
   1,671.31/2,507.39 = 978.56/x
3. Step 3: Cross multiply
   1,671.31x = 2,507.39 × 978.56
4. Step 4: Simplify right side
   1,671.31x = 2,453,631.56
5. Step 5: Solve for x
   x = 2,453,631.56/1,671.31
6. Step 6: Final answer
   x = 1,468.09