Finding the Fourth Proportional to 2,007.87, 3,012.13 and 620.88

Step by Step Solution

1. Step 1: Write the proportion equation
   2,007.87 : 3,012.13 = 620.88 : x
2. Step 2: Convert to fraction form
   2,007.87/3,012.13 = 620.88/x
3. Step 3: Cross multiply
   2,007.87x = 3,012.13 × 620.88
4. Step 4: Simplify right side
   2,007.87x = 1,870,171.27
5. Step 5: Solve for x
   x = 1,870,171.27/2,007.87
6. Step 6: Final answer
   x = 931.42