Finding the Fourth Proportional to 1,391.01, 1,919.61 and 801.51

Step by Step Solution

1. Step 1: Write the proportion equation
   1,391.01 : 1,919.61 = 801.51 : x
2. Step 2: Convert to fraction form
   1,391.01/1,919.61 = 801.51/x
3. Step 3: Cross multiply
   1,391.01x = 1,919.61 × 801.51
4. Step 4: Simplify right side
   1,391.01x = 1,538,586.61
5. Step 5: Solve for x
   x = 1,538,586.61/1,391.01
6. Step 6: Final answer
   x = 1,106.09