Finding the Third Proportional to 156.30 and 221.48

Step by Step Solution

1. Step 1: Write the proportion equation
   156.30 : 221.48 = 221.48 : x
2. Step 2: Convert to fraction form
   156.30/221.48 = 221.48/x
3. Step 3: Cross multiply
   156.30x = 221.48 × 221.48
4. Step 4: Simplify right side
   156.30x = 49,055.33
5. Step 5: Solve for x
   x = 49,055.33/156.30
6. Step 6: Final answer
   x = 313.84