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Finding the Fourth Proportional to 638.76, 956.61 and 330.18

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Solution

The fourth proportional to 638.76, 956.61 and 330.18 is: 494.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.76 : 956.61 = 330.18 : x
  2. Step 2: Convert to fraction form
    638.76/956.61 = 330.18/x
  3. Step 3: Cross multiply
    638.76x = 956.61 × 330.18
  4. Step 4: Simplify right side
    638.76x = 315,853.49
  5. Step 5: Solve for x
    x = 315,853.49/638.76
  6. Step 6: Final answer
    x = 494.48

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.