Finding the Third Proportional to 131.63 and 290.13

Step by Step Solution

1. Step 1: Write the proportion equation
   131.63 : 290.13 = 290.13 : x
2. Step 2: Convert to fraction form
   131.63/290.13 = 290.13/x
3. Step 3: Cross multiply
   131.63x = 290.13 × 290.13
4. Step 4: Simplify right side
   131.63x = 84,172.52
5. Step 5: Solve for x
   x = 84,172.52/131.63
6. Step 6: Final answer
   x = 639.49