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Finding the Fourth Proportional to 39.65, 54.55 and 39.47

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Solution

The fourth proportional to 39.65, 54.55 and 39.47 is: 54.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.65 : 54.55 = 39.47 : x
  2. Step 2: Convert to fraction form
    39.65/54.55 = 39.47/x
  3. Step 3: Cross multiply
    39.65x = 54.55 × 39.47
  4. Step 4: Simplify right side
    39.65x = 2,153.09
  5. Step 5: Solve for x
    x = 2,153.09/39.65
  6. Step 6: Final answer
    x = 54.30

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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.