Finding the Fourth Proportional to 1,393.20, 2,086.20 and 900.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,393.20 : 2,086.20 = 900.09 : x
2. Step 2: Convert to fraction form
   1,393.20/2,086.20 = 900.09/x
3. Step 3: Cross multiply
   1,393.20x = 2,086.20 × 900.09
4. Step 4: Simplify right side
   1,393.20x = 1,877,767.76
5. Step 5: Solve for x
   x = 1,877,767.76/1,393.20
6. Step 6: Final answer
   x = 1,347.81