Finding the Fourth Proportional to 123,871, 170,912.66 and 72,885.96

Step by Step Solution

1. Step 1: Write the proportion equation
   123,871 : 170,912.66 = 72,885.96 : x
2. Step 2: Convert to fraction form
   123,871/170,912.66 = 72,885.96/x
3. Step 3: Cross multiply
   123,871x = 170,912.66 × 72,885.96
4. Step 4: Simplify right side
   123,871x = 12,457,133,300.25
5. Step 5: Solve for x
   x = 12,457,133,300.25/123,871
6. Step 6: Final answer
   x = 100,565.37