Finding the Fourth Proportional to 1,355.42, 1,870.47 and 766.07

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.42 : 1,870.47 = 766.07 : x
2. Step 2: Convert to fraction form
   1,355.42/1,870.47 = 766.07/x
3. Step 3: Cross multiply
   1,355.42x = 1,870.47 × 766.07
4. Step 4: Simplify right side
   1,355.42x = 1,432,910.95
5. Step 5: Solve for x
   x = 1,432,910.95/1,355.42
6. Step 6: Final answer
   x = 1,057.17