Finding the Fourth Proportional to 1,370.15, 1,890.35 and 780.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,370.15 : 1,890.35 = 780.27 : x
2. Step 2: Convert to fraction form
   1,370.15/1,890.35 = 780.27/x
3. Step 3: Cross multiply
   1,370.15x = 1,890.35 × 780.27
4. Step 4: Simplify right side
   1,370.15x = 1,474,982.42
5. Step 5: Solve for x
   x = 1,474,982.42/1,370.15
6. Step 6: Final answer
   x = 1,076.51