Finding the Third Proportional to 64.50 and 99.88

Step by Step Solution

1. Step 1: Write the proportion equation
   64.50 : 99.88 = 99.88 : x
2. Step 2: Convert to fraction form
   64.50/99.88 = 99.88/x
3. Step 3: Cross multiply
   64.50x = 99.88 × 99.88
4. Step 4: Simplify right side
   64.50x = 9,975.02
5. Step 5: Solve for x
   x = 9,975.02/64.50
6. Step 6: Final answer
   x = 154.65