Finding the Fourth Proportional to 1,677.96, 2,315.52 and 921.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,677.96 : 2,315.52 = 921.78 : x
2. Step 2: Convert to fraction form
   1,677.96/2,315.52 = 921.78/x
3. Step 3: Cross multiply
   1,677.96x = 2,315.52 × 921.78
4. Step 4: Simplify right side
   1,677.96x = 2,134,400.03
5. Step 5: Solve for x
   x = 2,134,400.03/1,677.96
6. Step 6: Final answer
   x = 1,272.02