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Finding the Third Proportional to 287.50 and 408.75

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Solution

The third proportional to 287.50 and 408.75 is: 581.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.50 : 408.75 = 408.75 : x
  2. Step 2: Convert to fraction form
    287.50/408.75 = 408.75/x
  3. Step 3: Cross multiply
    287.50x = 408.75 × 408.75
  4. Step 4: Simplify right side
    287.50x = 167,076.56
  5. Step 5: Solve for x
    x = 167,076.56/287.50
  6. Step 6: Final answer
    x = 581.14

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Why These Related Problems?

These problems maintain the same ratio (1.42) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.