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Finding the Third Proportional to 121.13 and 257.81

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Solution

The third proportional to 121.13 and 257.81 is: 548.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    121.13 : 257.81 = 257.81 : x
  2. Step 2: Convert to fraction form
    121.13/257.81 = 257.81/x
  3. Step 3: Cross multiply
    121.13x = 257.81 × 257.81
  4. Step 4: Simplify right side
    121.13x = 66,467.29
  5. Step 5: Solve for x
    x = 66,467.29/121.13
  6. Step 6: Final answer
    x = 548.75

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Why These Related Problems?

These problems maintain the same ratio (2.13) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.