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Finding the Fourth Proportional to 63.65, 87.79 and 39.07

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Solution

The fourth proportional to 63.65, 87.79 and 39.07 is: 53.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    63.65 : 87.79 = 39.07 : x
  2. Step 2: Convert to fraction form
    63.65/87.79 = 39.07/x
  3. Step 3: Cross multiply
    63.65x = 87.79 × 39.07
  4. Step 4: Simplify right side
    63.65x = 3,429.96
  5. Step 5: Solve for x
    x = 3,429.96/63.65
  6. Step 6: Final answer
    x = 53.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.