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Finding the Fourth Proportional to 306.60, 425.61 and 287.16

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Solution

The fourth proportional to 306.60, 425.61 and 287.16 is: 398.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.60 : 425.61 = 287.16 : x
  2. Step 2: Convert to fraction form
    306.60/425.61 = 287.16/x
  3. Step 3: Cross multiply
    306.60x = 425.61 × 287.16
  4. Step 4: Simplify right side
    306.60x = 122,218.17
  5. Step 5: Solve for x
    x = 122,218.17/306.60
  6. Step 6: Final answer
    x = 398.62

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.