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Finding the Fourth Proportional to 65.30, 90.12 and 39.06

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Solution

The fourth proportional to 65.30, 90.12 and 39.06 is: 53.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.30 : 90.12 = 39.06 : x
  2. Step 2: Convert to fraction form
    65.30/90.12 = 39.06/x
  3. Step 3: Cross multiply
    65.30x = 90.12 × 39.06
  4. Step 4: Simplify right side
    65.30x = 3,520.09
  5. Step 5: Solve for x
    x = 3,520.09/65.30
  6. Step 6: Final answer
    x = 53.91

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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.