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Finding the Fourth Proportional to 638.35, 957.55 and 199.65

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Solution

The fourth proportional to 638.35, 957.55 and 199.65 is: 299.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.35 : 957.55 = 199.65 : x
  2. Step 2: Convert to fraction form
    638.35/957.55 = 199.65/x
  3. Step 3: Cross multiply
    638.35x = 957.55 × 199.65
  4. Step 4: Simplify right side
    638.35x = 191,174.86
  5. Step 5: Solve for x
    x = 191,174.86/638.35
  6. Step 6: Final answer
    x = 299.48

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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.