Finding the Fourth Proportional to 1,315.92, 1,970.78 and 1,040.16

Step by Step Solution

1. Step 1: Write the proportion equation
   1,315.92 : 1,970.78 = 1,040.16 : x
2. Step 2: Convert to fraction form
   1,315.92/1,970.78 = 1,040.16/x
3. Step 3: Cross multiply
   1,315.92x = 1,970.78 × 1,040.16
4. Step 4: Simplify right side
   1,315.92x = 2,049,926.52
5. Step 5: Solve for x
   x = 2,049,926.52/1,315.92
6. Step 6: Final answer
   x = 1,557.79