Finding the Fourth Proportional to 2,142.72, 2,956.80 and 1,678.08

Step by Step Solution

1. Step 1: Write the proportion equation
   2,142.72 : 2,956.80 = 1,678.08 : x
2. Step 2: Convert to fraction form
   2,142.72/2,956.80 = 1,678.08/x
3. Step 3: Cross multiply
   2,142.72x = 2,956.80 × 1,678.08
4. Step 4: Simplify right side
   2,142.72x = 4,961,746.94
5. Step 5: Solve for x
   x = 4,961,746.94/2,142.72
6. Step 6: Final answer
   x = 2,315.63