Finding the Third Proportional to 17,720 and 31,312

Step by Step Solution

1. Step 1: Write the proportion equation
   17,720 : 31,312 = 31,312 : x
2. Step 2: Convert to fraction form
   17,720/31,312 = 31,312/x
3. Step 3: Cross multiply
   17,720x = 31,312 × 31,312
4. Step 4: Simplify right side
   17,720x = 980,441,344
5. Step 5: Solve for x
   x = 980,441,344/17,720
6. Step 6: Final answer
   x = 55,329.65