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Finding the Third Proportional to 290.81 and 428.06

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Solution

The third proportional to 290.81 and 428.06 is: 630.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.81 : 428.06 = 428.06 : x
  2. Step 2: Convert to fraction form
    290.81/428.06 = 428.06/x
  3. Step 3: Cross multiply
    290.81x = 428.06 × 428.06
  4. Step 4: Simplify right side
    290.81x = 183,237.50
  5. Step 5: Solve for x
    x = 183,237.50/290.81
  6. Step 6: Final answer
    x = 630.09

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Why These Related Problems?

These problems maintain the same ratio (1.47) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.