Finding the Fourth Proportional to 1,393.60, 1,923.04 and 772.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,393.60 : 1,923.04 = 772.48 : x
2. Step 2: Convert to fraction form
   1,393.60/1,923.04 = 772.48/x
3. Step 3: Cross multiply
   1,393.60x = 1,923.04 × 772.48
4. Step 4: Simplify right side
   1,393.60x = 1,485,509.94
5. Step 5: Solve for x
   x = 1,485,509.94/1,393.60
6. Step 6: Final answer
   x = 1,065.95