Finding the Fourth Proportional to 1,918.72, 2,878.56 and 764.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,918.72 : 2,878.56 = 764.56 : x
2. Step 2: Convert to fraction form
   1,918.72/2,878.56 = 764.56/x
3. Step 3: Cross multiply
   1,918.72x = 2,878.56 × 764.56
4. Step 4: Simplify right side
   1,918.72x = 2,200,831.83
5. Step 5: Solve for x
   x = 2,200,831.83/1,918.72
6. Step 6: Final answer
   x = 1,147.03