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Finding the Fourth Proportional to 643.05, 963.81 and 278.10

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Solution

The fourth proportional to 643.05, 963.81 and 278.10 is: 416.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.05 : 963.81 = 278.10 : x
  2. Step 2: Convert to fraction form
    643.05/963.81 = 278.10/x
  3. Step 3: Cross multiply
    643.05x = 963.81 × 278.10
  4. Step 4: Simplify right side
    643.05x = 268,035.56
  5. Step 5: Solve for x
    x = 268,035.56/643.05
  6. Step 6: Final answer
    x = 416.82

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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.