Finding the Fourth Proportional to 1,620.99, 2,428.69 and 1,276.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,620.99 : 2,428.69 = 1,276.53 : x
2. Step 2: Convert to fraction form
   1,620.99/2,428.69 = 1,276.53/x
3. Step 3: Cross multiply
   1,620.99x = 2,428.69 × 1,276.53
4. Step 4: Simplify right side
   1,620.99x = 3,100,295.65
5. Step 5: Solve for x
   x = 3,100,295.65/1,620.99
6. Step 6: Final answer
   x = 1,912.59