Finding the Fourth Proportional to 1,962.50, 2,707.90 and 1,439.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,962.50 : 2,707.90 = 1,439.78 : x
2. Step 2: Convert to fraction form
   1,962.50/2,707.90 = 1,439.78/x
3. Step 3: Cross multiply
   1,962.50x = 2,707.90 × 1,439.78
4. Step 4: Simplify right side
   1,962.50x = 3,898,763.12
5. Step 5: Solve for x
   x = 3,898,763.12/1,962.50
6. Step 6: Final answer
   x = 1,986.64