Finding the Fourth Proportional to 2,638.63, 3,955.15 and 994.47

Step by Step Solution

1. Step 1: Write the proportion equation
   2,638.63 : 3,955.15 = 994.47 : x
2. Step 2: Convert to fraction form
   2,638.63/3,955.15 = 994.47/x
3. Step 3: Cross multiply
   2,638.63x = 3,955.15 × 994.47
4. Step 4: Simplify right side
   2,638.63x = 3,933,278.02
5. Step 5: Solve for x
   x = 3,933,278.02/2,638.63
6. Step 6: Final answer
   x = 1,490.65