Finding the Fourth Proportional to 1,290.69, 1,936.83 and 510.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.69 : 1,936.83 = 510.56 : x
2. Step 2: Convert to fraction form
   1,290.69/1,936.83 = 510.56/x
3. Step 3: Cross multiply
   1,290.69x = 1,936.83 × 510.56
4. Step 4: Simplify right side
   1,290.69x = 988,865.50
5. Step 5: Solve for x
   x = 988,865.50/1,290.69
6. Step 6: Final answer
   x = 766.15