Finding the Fourth Proportional to 1,345.74, 1,855.20 and 1,047.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,345.74 : 1,855.20 = 1,047.39 : x
2. Step 2: Convert to fraction form
   1,345.74/1,855.20 = 1,047.39/x
3. Step 3: Cross multiply
   1,345.74x = 1,855.20 × 1,047.39
4. Step 4: Simplify right side
   1,345.74x = 1,943,117.93
5. Step 5: Solve for x
   x = 1,943,117.93/1,345.74
6. Step 6: Final answer
   x = 1,443.90