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Finding the Fourth Proportional to 644.48, 965.96 and 278.72

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Solution

The fourth proportional to 644.48, 965.96 and 278.72 is: 417.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    644.48 : 965.96 = 278.72 : x
  2. Step 2: Convert to fraction form
    644.48/965.96 = 278.72/x
  3. Step 3: Cross multiply
    644.48x = 965.96 × 278.72
  4. Step 4: Simplify right side
    644.48x = 269,232.37
  5. Step 5: Solve for x
    x = 269,232.37/644.48
  6. Step 6: Final answer
    x = 417.75

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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.