Finding the Fourth Proportional to 1,390.32, 1,918.56 and 801.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,390.32 : 1,918.56 = 801.24 : x
2. Step 2: Convert to fraction form
   1,390.32/1,918.56 = 801.24/x
3. Step 3: Cross multiply
   1,390.32x = 1,918.56 × 801.24
4. Step 4: Simplify right side
   1,390.32x = 1,537,227.01
5. Step 5: Solve for x
   x = 1,537,227.01/1,390.32
6. Step 6: Final answer
   x = 1,105.66