Finding the Fourth Proportional to 978.17, 1,459.67 and 874.31

Step by Step Solution

1. Step 1: Write the proportion equation
   978.17 : 1,459.67 = 874.31 : x
2. Step 2: Convert to fraction form
   978.17/1,459.67 = 874.31/x
3. Step 3: Cross multiply
   978.17x = 1,459.67 × 874.31
4. Step 4: Simplify right side
   978.17x = 1,276,211.55
5. Step 5: Solve for x
   x = 1,276,211.55/978.17
6. Step 6: Final answer
   x = 1,304.69