Finding the Fourth Proportional to 1,440.72, 1,987.34 and 1,086.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,440.72 : 1,987.34 = 1,086.48 : x
2. Step 2: Convert to fraction form
   1,440.72/1,987.34 = 1,086.48/x
3. Step 3: Cross multiply
   1,440.72x = 1,987.34 × 1,086.48
4. Step 4: Simplify right side
   1,440.72x = 2,159,199.73
5. Step 5: Solve for x
   x = 2,159,199.73/1,440.72
6. Step 6: Final answer
   x = 1,498.69