Finding the Third Proportional to 210,142 and 315,429

Step by Step Solution

1. Step 1: Write the proportion equation
   210,142 : 315,429 = 315,429 : x
2. Step 2: Convert to fraction form
   210,142/315,429 = 315,429/x
3. Step 3: Cross multiply
   210,142x = 315,429 × 315,429
4. Step 4: Simplify right side
   210,142x = 99,495,454,041
5. Step 5: Solve for x
   x = 99,495,454,041/210,142
6. Step 6: Final answer
   x = 473,467.72