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Finding the Fourth Proportional to 65.71, 90.66 and 39.49

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Solution

The fourth proportional to 65.71, 90.66 and 39.49 is: 54.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.71 : 90.66 = 39.49 : x
  2. Step 2: Convert to fraction form
    65.71/90.66 = 39.49/x
  3. Step 3: Cross multiply
    65.71x = 90.66 × 39.49
  4. Step 4: Simplify right side
    65.71x = 3,580.08
  5. Step 5: Solve for x
    x = 3,580.08/65.71
  6. Step 6: Final answer
    x = 54.48

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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.