Finding the Fourth Proportional to 1,396.88, 1,927.71 and 807.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,396.88 : 1,927.71 = 807.60 : x
2. Step 2: Convert to fraction form
   1,396.88/1,927.71 = 807.60/x
3. Step 3: Cross multiply
   1,396.88x = 1,927.71 × 807.60
4. Step 4: Simplify right side
   1,396.88x = 1,556,818.60
5. Step 5: Solve for x
   x = 1,556,818.60/1,396.88
6. Step 6: Final answer
   x = 1,114.50