Finding the Fourth Proportional to 1,380.50, 1,908.69 and 1,319.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.50 : 1,908.69 = 1,319.30 : x
2. Step 2: Convert to fraction form
   1,380.50/1,908.69 = 1,319.30/x
3. Step 3: Cross multiply
   1,380.50x = 1,908.69 × 1,319.30
4. Step 4: Simplify right side
   1,380.50x = 2,518,134.72
5. Step 5: Solve for x
   x = 2,518,134.72/1,380.50
6. Step 6: Final answer
   x = 1,824.07