Finding the Fourth Proportional to 124.34, 171.72 and 123.12

Step by Step Solution

1. Step 1: Write the proportion equation
   124.34 : 171.72 = 123.12 : x
2. Step 2: Convert to fraction form
   124.34/171.72 = 123.12/x
3. Step 3: Cross multiply
   124.34x = 171.72 × 123.12
4. Step 4: Simplify right side
   124.34x = 21,142.17
5. Step 5: Solve for x
   x = 21,142.17/124.34
6. Step 6: Final answer
   x = 170.04