Finding the Fourth Proportional to 1,558.72, 2,150.28 and 961.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,558.72 : 2,150.28 = 961.40 : x
2. Step 2: Convert to fraction form
   1,558.72/2,150.28 = 961.40/x
3. Step 3: Cross multiply
   1,558.72x = 2,150.28 × 961.40
4. Step 4: Simplify right side
   1,558.72x = 2,067,279.19
5. Step 5: Solve for x
   x = 2,067,279.19/1,558.72
6. Step 6: Final answer
   x = 1,326.27