Finding the Fourth Proportional to 1,390.09, 1,907.37 and 1,377.03

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.09 : 1,907.37 = 1,377.03 : x
2. Step 2: Convert to fraction form
   1,390.09/1,907.37 = 1,377.03/x
3. Step 3: Cross multiply
   1,390.09x = 1,907.37 × 1,377.03
4. Step 4: Simplify right side
   1,390.09x = 2,626,498.83
5. Step 5: Solve for x
   x = 2,626,498.83/1,390.09
6. Step 6: Final answer
   x = 1,889.45