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Finding the Fourth Proportional to 42.65, 63.69 and 39

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Solution

The fourth proportional to 42.65, 63.69 and 39 is: 58.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.65 : 63.69 = 39 : x
  2. Step 2: Convert to fraction form
    42.65/63.69 = 39/x
  3. Step 3: Cross multiply
    42.65x = 63.69 × 39
  4. Step 4: Simplify right side
    42.65x = 2,483.91
  5. Step 5: Solve for x
    x = 2,483.91/42.65
  6. Step 6: Final answer
    x = 58.25

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.