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Finding the Fourth Proportional to 638.39, 957.56 and 199.64

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Solution

The fourth proportional to 638.39, 957.56 and 199.64 is: 299.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.39 : 957.56 = 199.64 : x
  2. Step 2: Convert to fraction form
    638.39/957.56 = 199.64/x
  3. Step 3: Cross multiply
    638.39x = 957.56 × 199.64
  4. Step 4: Simplify right side
    638.39x = 191,161.49
  5. Step 5: Solve for x
    x = 191,161.49/638.39
  6. Step 6: Final answer
    x = 299.45

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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.