Finding the Fourth Proportional to 1,359.99, 1,877.12 and 770.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,359.99 : 1,877.12 = 770.87 : x
2. Step 2: Convert to fraction form
   1,359.99/1,877.12 = 770.87/x
3. Step 3: Cross multiply
   1,359.99x = 1,877.12 × 770.87
4. Step 4: Simplify right side
   1,359.99x = 1,447,015.49
5. Step 5: Solve for x
   x = 1,447,015.49/1,359.99
6. Step 6: Final answer
   x = 1,063.99