Finding the Fourth Proportional to 1,876.83, 2,815.69 and 644.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,876.83 : 2,815.69 = 644.25 : x
2. Step 2: Convert to fraction form
   1,876.83/2,815.69 = 644.25/x
3. Step 3: Cross multiply
   1,876.83x = 2,815.69 × 644.25
4. Step 4: Simplify right side
   1,876.83x = 1,814,016.63
5. Step 5: Solve for x
   x = 1,814,016.63/1,876.83
6. Step 6: Final answer
   x = 966.53