Finding the Fourth Proportional to 1,678.21, 2,315.81 and 932.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,678.21 : 2,315.81 = 932.12 : x
2. Step 2: Convert to fraction form
   1,678.21/2,315.81 = 932.12/x
3. Step 3: Cross multiply
   1,678.21x = 2,315.81 × 932.12
4. Step 4: Simplify right side
   1,678.21x = 2,158,612.82
5. Step 5: Solve for x
   x = 2,158,612.82/1,678.21
6. Step 6: Final answer
   x = 1,286.26