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Finding the Fourth Proportional to 678.87, 936.85 and 380.13

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Solution

The fourth proportional to 678.87, 936.85 and 380.13 is: 524.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.87 : 936.85 = 380.13 : x
  2. Step 2: Convert to fraction form
    678.87/936.85 = 380.13/x
  3. Step 3: Cross multiply
    678.87x = 936.85 × 380.13
  4. Step 4: Simplify right side
    678.87x = 356,122.89
  5. Step 5: Solve for x
    x = 356,122.89/678.87
  6. Step 6: Final answer
    x = 524.58

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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.