Finding the Fourth Proportional to 1,404.65, 1,938.43 and 775.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,404.65 : 1,938.43 = 775.20 : x
2. Step 2: Convert to fraction form
   1,404.65/1,938.43 = 775.20/x
3. Step 3: Cross multiply
   1,404.65x = 1,938.43 × 775.20
4. Step 4: Simplify right side
   1,404.65x = 1,502,670.94
5. Step 5: Solve for x
   x = 1,502,670.94/1,404.65
6. Step 6: Final answer
   x = 1,069.78