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Finding the Fourth Proportional to 638.34, 880.90 and 358.60

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Solution

The fourth proportional to 638.34, 880.90 and 358.60 is: 494.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.34 : 880.90 = 358.60 : x
  2. Step 2: Convert to fraction form
    638.34/880.90 = 358.60/x
  3. Step 3: Cross multiply
    638.34x = 880.90 × 358.60
  4. Step 4: Simplify right side
    638.34x = 315,890.74
  5. Step 5: Solve for x
    x = 315,890.74/638.34
  6. Step 6: Final answer
    x = 494.86

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1.5x scale

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.