Finding the Fourth Proportional to 1,038.88, 1,433.72 and 646.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,038.88 : 1,433.72 = 646.16 : x
2. Step 2: Convert to fraction form
   1,038.88/1,433.72 = 646.16/x
3. Step 3: Cross multiply
   1,038.88x = 1,433.72 × 646.16
4. Step 4: Simplify right side
   1,038.88x = 926,412.52
5. Step 5: Solve for x
   x = 926,412.52/1,038.88
6. Step 6: Final answer
   x = 891.74