Finding the Third Proportional to 139,090.50 and 211,288.50

Step by Step Solution

1. Step 1: Write the proportion equation
   139,090.50 : 211,288.50 = 211,288.50 : x
2. Step 2: Convert to fraction form
   139,090.50/211,288.50 = 211,288.50/x
3. Step 3: Cross multiply
   139,090.50x = 211,288.50 × 211,288.50
4. Step 4: Simplify right side
   139,090.50x = 44,642,830,232.25
5. Step 5: Solve for x
   x = 44,642,830,232.25/139,090.50
6. Step 6: Final answer
   x = 320,962.47