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Finding the Fourth Proportional to 638.15, 956.90 and 291.25

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Solution

The fourth proportional to 638.15, 956.90 and 291.25 is: 436.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.15 : 956.90 = 291.25 : x
  2. Step 2: Convert to fraction form
    638.15/956.90 = 291.25/x
  3. Step 3: Cross multiply
    638.15x = 956.90 × 291.25
  4. Step 4: Simplify right side
    638.15x = 278,692.34
  5. Step 5: Solve for x
    x = 278,692.34/638.15
  6. Step 6: Final answer
    x = 436.72

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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.