Finding the Fourth Proportional to 2,988.47, 4,480.94 and 1,139.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,988.47 : 4,480.94 = 1,139.72 : x
2. Step 2: Convert to fraction form
   2,988.47/4,480.94 = 1,139.72/x
3. Step 3: Cross multiply
   2,988.47x = 4,480.94 × 1,139.72
4. Step 4: Simplify right side
   2,988.47x = 5,106,997.38
5. Step 5: Solve for x
   x = 5,106,997.38/2,988.47
6. Step 6: Final answer
   x = 1,708.90