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Finding the Fourth Proportional to 638.32, 880.86 and 428.92

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Solution

The fourth proportional to 638.32, 880.86 and 428.92 is: 591.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.32 : 880.86 = 428.92 : x
  2. Step 2: Convert to fraction form
    638.32/880.86 = 428.92/x
  3. Step 3: Cross multiply
    638.32x = 880.86 × 428.92
  4. Step 4: Simplify right side
    638.32x = 377,818.47
  5. Step 5: Solve for x
    x = 377,818.47/638.32
  6. Step 6: Final answer
    x = 591.90

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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.