Finding the Fourth Proportional to 1,441.20, 1,986.72 and 916.32

Step by Step Solution

1. Step 1: Write the proportion equation
   1,441.20 : 1,986.72 = 916.32 : x
2. Step 2: Convert to fraction form
   1,441.20/1,986.72 = 916.32/x
3. Step 3: Cross multiply
   1,441.20x = 1,986.72 × 916.32
4. Step 4: Simplify right side
   1,441.20x = 1,820,471.27
5. Step 5: Solve for x
   x = 1,820,471.27/1,441.20
6. Step 6: Final answer
   x = 1,263.16