Finding the Fourth Proportional to 2,388.49, 3,581.58 and 999.91

Step by Step Solution

1. Step 1: Write the proportion equation
   2,388.49 : 3,581.58 = 999.91 : x
2. Step 2: Convert to fraction form
   2,388.49/3,581.58 = 999.91/x
3. Step 3: Cross multiply
   2,388.49x = 3,581.58 × 999.91
4. Step 4: Simplify right side
   2,388.49x = 3,581,259.60
5. Step 5: Solve for x
   x = 3,581,259.60/2,388.49
6. Step 6: Final answer
   x = 1,499.38