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Finding the Fourth Proportional to 425.68, 638 and 208.96

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Solution

The fourth proportional to 425.68, 638 and 208.96 is: 313.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.68 : 638 = 208.96 : x
  2. Step 2: Convert to fraction form
    425.68/638 = 208.96/x
  3. Step 3: Cross multiply
    425.68x = 638 × 208.96
  4. Step 4: Simplify right side
    425.68x = 133,316.48
  5. Step 5: Solve for x
    x = 133,316.48/425.68
  6. Step 6: Final answer
    x = 313.18

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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.