Finding the Fourth Proportional to 1,380.48, 2,066.46 and 801.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.48 : 2,066.46 = 801.60 : x
2. Step 2: Convert to fraction form
   1,380.48/2,066.46 = 801.60/x
3. Step 3: Cross multiply
   1,380.48x = 2,066.46 × 801.60
4. Step 4: Simplify right side
   1,380.48x = 1,656,474.34
5. Step 5: Solve for x
   x = 1,656,474.34/1,380.48
6. Step 6: Final answer
   x = 1,199.93