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Finding the Fourth Proportional to 678.39, 936.83 and 469.09

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Solution

The fourth proportional to 678.39, 936.83 and 469.09 is: 647.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.39 : 936.83 = 469.09 : x
  2. Step 2: Convert to fraction form
    678.39/936.83 = 469.09/x
  3. Step 3: Cross multiply
    678.39x = 936.83 × 469.09
  4. Step 4: Simplify right side
    678.39x = 439,457.58
  5. Step 5: Solve for x
    x = 439,457.58/678.39
  6. Step 6: Final answer
    x = 647.79

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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.