Finding the Fourth Proportional to 1,056.72, 1,458.28 and 636.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,056.72 : 1,458.28 = 636.99 : x
2. Step 2: Convert to fraction form
   1,056.72/1,458.28 = 636.99/x
3. Step 3: Cross multiply
   1,056.72x = 1,458.28 × 636.99
4. Step 4: Simplify right side
   1,056.72x = 928,910.10
5. Step 5: Solve for x
   x = 928,910.10/1,056.72
6. Step 6: Final answer
   x = 879.05