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Finding the Fourth Proportional to 678.89, 936.87 and 384.15

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Solution

The fourth proportional to 678.89, 936.87 and 384.15 is: 530.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.89 : 936.87 = 384.15 : x
  2. Step 2: Convert to fraction form
    678.89/936.87 = 384.15/x
  3. Step 3: Cross multiply
    678.89x = 936.87 × 384.15
  4. Step 4: Simplify right side
    678.89x = 359,898.61
  5. Step 5: Solve for x
    x = 359,898.61/678.89
  6. Step 6: Final answer
    x = 530.13

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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.