Finding the Fourth Proportional to 1,290.42, 1,935.83 and 510.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,290.42 : 1,935.83 = 510.42 : x
2. Step 2: Convert to fraction form
   1,290.42/1,935.83 = 510.42/x
3. Step 3: Cross multiply
   1,290.42x = 1,935.83 × 510.42
4. Step 4: Simplify right side
   1,290.42x = 988,086.35
5. Step 5: Solve for x
   x = 988,086.35/1,290.42
6. Step 6: Final answer
   x = 765.71