Finding the Fourth Proportional to 1,435.40, 1,980.86 and 805.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,435.40 : 1,980.86 = 805.99 : x
2. Step 2: Convert to fraction form
   1,435.40/1,980.86 = 805.99/x
3. Step 3: Cross multiply
   1,435.40x = 1,980.86 × 805.99
4. Step 4: Simplify right side
   1,435.40x = 1,596,548.08
5. Step 5: Solve for x
   x = 1,596,548.08/1,435.40
6. Step 6: Final answer
   x = 1,112.26