Finding the Fourth Proportional to 1,366.80, 1,886.10 and 777.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,366.80 : 1,886.10 = 777.42 : x
2. Step 2: Convert to fraction form
   1,366.80/1,886.10 = 777.42/x
3. Step 3: Cross multiply
   1,366.80x = 1,886.10 × 777.42
4. Step 4: Simplify right side
   1,366.80x = 1,466,291.86
5. Step 5: Solve for x
   x = 1,466,291.86/1,366.80
6. Step 6: Final answer
   x = 1,072.79