Finding the Fourth Proportional to 978.21, 1,464.89 and 631.53

Step by Step Solution

1. Step 1: Write the proportion equation
   978.21 : 1,464.89 = 631.53 : x
2. Step 2: Convert to fraction form
   978.21/1,464.89 = 631.53/x
3. Step 3: Cross multiply
   978.21x = 1,464.89 × 631.53
4. Step 4: Simplify right side
   978.21x = 925,118.82
5. Step 5: Solve for x
   x = 925,118.82/978.21
6. Step 6: Final answer
   x = 945.73