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Finding the Fourth Proportional to 678.65, 936.30 and 383.85

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Solution

The fourth proportional to 678.65, 936.30 and 383.85 is: 529.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.65 : 936.30 = 383.85 : x
  2. Step 2: Convert to fraction form
    678.65/936.30 = 383.85/x
  3. Step 3: Cross multiply
    678.65x = 936.30 × 383.85
  4. Step 4: Simplify right side
    678.65x = 359,398.76
  5. Step 5: Solve for x
    x = 359,398.76/678.65
  6. Step 6: Final answer
    x = 529.58

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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.