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Finding the Fourth Proportional to 451.70, 678.17 and 208.70

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Solution

The fourth proportional to 451.70, 678.17 and 208.70 is: 313.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    451.70 : 678.17 = 208.70 : x
  2. Step 2: Convert to fraction form
    451.70/678.17 = 208.70/x
  3. Step 3: Cross multiply
    451.70x = 678.17 × 208.70
  4. Step 4: Simplify right side
    451.70x = 141,531.21
  5. Step 5: Solve for x
    x = 141,531.21/451.70
  6. Step 6: Final answer
    x = 313.33

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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.