Finding the Third Proportional to 99.84 and 258.05

Step by Step Solution

1. Step 1: Write the proportion equation
   99.84 : 258.05 = 258.05 : x
2. Step 2: Convert to fraction form
   99.84/258.05 = 258.05/x
3. Step 3: Cross multiply
   99.84x = 258.05 × 258.05
4. Step 4: Simplify right side
   99.84x = 66,588.19
5. Step 5: Solve for x
   x = 66,588.19/99.84
6. Step 6: Final answer
   x = 666.92