Finding the Third Proportional to 142,911 and 210,090

Step by Step Solution

1. Step 1: Write the proportion equation
   142,911 : 210,090 = 210,090 : x
2. Step 2: Convert to fraction form
   142,911/210,090 = 210,090/x
3. Step 3: Cross multiply
   142,911x = 210,090 × 210,090
4. Step 4: Simplify right side
   142,911x = 44,137,808,100
5. Step 5: Solve for x
   x = 44,137,808,100/142,911
6. Step 6: Final answer
   x = 308,848.22