Finding the Fourth Proportional to 1,388.69, 1,916.42 and 799.23

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.69 : 1,916.42 = 799.23 : x
2. Step 2: Convert to fraction form
   1,388.69/1,916.42 = 799.23/x
3. Step 3: Cross multiply
   1,388.69x = 1,916.42 × 799.23
4. Step 4: Simplify right side
   1,388.69x = 1,531,656.36
5. Step 5: Solve for x
   x = 1,531,656.36/1,388.69
6. Step 6: Final answer
   x = 1,102.95