Finding the Fourth Proportional to 1,390.63, 1,919.19 and 801.37

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.63 : 1,919.19 = 801.37 : x
2. Step 2: Convert to fraction form
   1,390.63/1,919.19 = 801.37/x
3. Step 3: Cross multiply
   1,390.63x = 1,919.19 × 801.37
4. Step 4: Simplify right side
   1,390.63x = 1,537,981.29
5. Step 5: Solve for x
   x = 1,537,981.29/1,390.63
6. Step 6: Final answer
   x = 1,105.96