Finding the Fourth Proportional to 1,440.50, 1,987.65 and 810.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,440.50 : 1,987.65 = 810.99 : x
2. Step 2: Convert to fraction form
   1,440.50/1,987.65 = 810.99/x
3. Step 3: Cross multiply
   1,440.50x = 1,987.65 × 810.99
4. Step 4: Simplify right side
   1,440.50x = 1,611,964.27
5. Step 5: Solve for x
   x = 1,611,964.27/1,440.50
6. Step 6: Final answer
   x = 1,119.03