Finding the Fourth Proportional to 1,355.34, 1,870.40 and 765.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.34 : 1,870.40 = 765.76 : x
2. Step 2: Convert to fraction form
   1,355.34/1,870.40 = 765.76/x
3. Step 3: Cross multiply
   1,355.34x = 1,870.40 × 765.76
4. Step 4: Simplify right side
   1,355.34x = 1,432,277.50
5. Step 5: Solve for x
   x = 1,432,277.50/1,355.34
6. Step 6: Final answer
   x = 1,056.77