Finding the Fourth Proportional to 2,642.87, 3,964.89 and 999.43

Step by Step Solution

1. Step 1: Write the proportion equation
   2,642.87 : 3,964.89 = 999.43 : x
2. Step 2: Convert to fraction form
   2,642.87/3,964.89 = 999.43/x
3. Step 3: Cross multiply
   2,642.87x = 3,964.89 × 999.43
4. Step 4: Simplify right side
   2,642.87x = 3,962,631.22
5. Step 5: Solve for x
   x = 3,962,631.22/2,642.87
6. Step 6: Final answer
   x = 1,499.37