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Finding the Fourth Proportional to 65.29, 90.09 and 39.08

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Solution

The fourth proportional to 65.29, 90.09 and 39.08 is: 53.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.29 : 90.09 = 39.08 : x
  2. Step 2: Convert to fraction form
    65.29/90.09 = 39.08/x
  3. Step 3: Cross multiply
    65.29x = 90.09 × 39.08
  4. Step 4: Simplify right side
    65.29x = 3,520.72
  5. Step 5: Solve for x
    x = 3,520.72/65.29
  6. Step 6: Final answer
    x = 53.92

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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.