Finding the Fourth Proportional to 2,139.39, 3,208.77 and 906.53

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.39 : 3,208.77 = 906.53 : x
2. Step 2: Convert to fraction form
   2,139.39/3,208.77 = 906.53/x
3. Step 3: Cross multiply
   2,139.39x = 3,208.77 × 906.53
4. Step 4: Simplify right side
   2,139.39x = 2,908,830.22
5. Step 5: Solve for x
   x = 2,908,830.22/2,139.39
6. Step 6: Final answer
   x = 1,359.65