Finding the Fourth Proportional to 1,679.14, 2,516.52 and 856.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,679.14 : 2,516.52 = 856.72 : x
2. Step 2: Convert to fraction form
   1,679.14/2,516.52 = 856.72/x
3. Step 3: Cross multiply
   1,679.14x = 2,516.52 × 856.72
4. Step 4: Simplify right side
   1,679.14x = 2,155,953.01
5. Step 5: Solve for x
   x = 2,155,953.01/1,679.14
6. Step 6: Final answer
   x = 1,283.96