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Finding the Fourth Proportional to 663.67, 915 and 427.20

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Solution

The fourth proportional to 663.67, 915 and 427.20 is: 588.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.67 : 915 = 427.20 : x
  2. Step 2: Convert to fraction form
    663.67/915 = 427.20/x
  3. Step 3: Cross multiply
    663.67x = 915 × 427.20
  4. Step 4: Simplify right side
    663.67x = 390,883.43
  5. Step 5: Solve for x
    x = 390,883.43/663.67
  6. Step 6: Final answer
    x = 588.97

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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.