Finding the Fourth Proportional to 1,368.15, 1,888.20 and 778.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,368.15 : 1,888.20 = 778.79 : x
2. Step 2: Convert to fraction form
   1,368.15/1,888.20 = 778.79/x
3. Step 3: Cross multiply
   1,368.15x = 1,888.20 × 778.79
4. Step 4: Simplify right side
   1,368.15x = 1,470,511.28
5. Step 5: Solve for x
   x = 1,470,511.28/1,368.15
6. Step 6: Final answer
   x = 1,074.82