Finding the Third Proportional to 142,899 and 210,215.50

Step by Step Solution

1. Step 1: Write the proportion equation
   142,899 : 210,215.50 = 210,215.50 : x
2. Step 2: Convert to fraction form
   142,899/210,215.50 = 210,215.50/x
3. Step 3: Cross multiply
   142,899x = 210,215.50 × 210,215.50
4. Step 4: Simplify right side
   142,899x = 44,190,556,440.25
5. Step 5: Solve for x
   x = 44,190,556,440.25/142,899
6. Step 6: Final answer
   x = 309,243.29