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Finding the Fourth Proportional to 644.15, 965.42 and 278.57

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Solution

The fourth proportional to 644.15, 965.42 and 278.57 is: 417.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.15 : 965.42 = 278.57 : x
  2. Step 2: Convert to fraction form
    644.15/965.42 = 278.57/x
  3. Step 3: Cross multiply
    644.15x = 965.42 × 278.57
  4. Step 4: Simplify right side
    644.15x = 268,939.11
  5. Step 5: Solve for x
    x = 268,939.11/644.15
  6. Step 6: Final answer
    x = 417.51

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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.