Finding the Fourth Proportional to 647.69, 971.69 and 214.82

Step by Step Solution

1. Step 1: Write the proportion equation
   647.69 : 971.69 = 214.82 : x
2. Step 2: Convert to fraction form
   647.69/971.69 = 214.82/x
3. Step 3: Cross multiply
   647.69x = 971.69 × 214.82
4. Step 4: Simplify right side
   647.69x = 208,737.37
5. Step 5: Solve for x
   x = 208,737.37/647.69
6. Step 6: Final answer
   x = 322.28