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Finding the Fourth Proportional to 638.69, 958.36 and 291.98

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Solution

The fourth proportional to 638.69, 958.36 and 291.98 is: 438.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.69 : 958.36 = 291.98 : x
  2. Step 2: Convert to fraction form
    638.69/958.36 = 291.98/x
  3. Step 3: Cross multiply
    638.69x = 958.36 × 291.98
  4. Step 4: Simplify right side
    638.69x = 279,821.95
  5. Step 5: Solve for x
    x = 279,821.95/638.69
  6. Step 6: Final answer
    x = 438.12

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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.