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Finding the Third Proportional to 290 and 399.25

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Solution

The third proportional to 290 and 399.25 is: 549.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    290 : 399.25 = 399.25 : x
  2. Step 2: Convert to fraction form
    290/399.25 = 399.25/x
  3. Step 3: Cross multiply
    290x = 399.25 × 399.25
  4. Step 4: Simplify right side
    290x = 159,400.56
  5. Step 5: Solve for x
    x = 159,400.56/290
  6. Step 6: Final answer
    x = 549.66

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.