Finding the Fourth Proportional to 1,005.95, 1,506.18 and 761.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,005.95 : 1,506.18 = 761.78 : x
2. Step 2: Convert to fraction form
   1,005.95/1,506.18 = 761.78/x
3. Step 3: Cross multiply
   1,005.95x = 1,506.18 × 761.78
4. Step 4: Simplify right side
   1,005.95x = 1,147,377.80
5. Step 5: Solve for x
   x = 1,147,377.80/1,005.95
6. Step 6: Final answer
   x = 1,140.59