Finding the Fourth Proportional to 1,321.72, 1,977.54 and 774.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,321.72 : 1,977.54 = 774.16 : x
2. Step 2: Convert to fraction form
   1,321.72/1,977.54 = 774.16/x
3. Step 3: Cross multiply
   1,321.72x = 1,977.54 × 774.16
4. Step 4: Simplify right side
   1,321.72x = 1,530,932.37
5. Step 5: Solve for x
   x = 1,530,932.37/1,321.72
6. Step 6: Final answer
   x = 1,158.29