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Finding the Fourth Proportional to 47.70, 65.80 and 28.30

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Solution

The fourth proportional to 47.70, 65.80 and 28.30 is: 39.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.70 : 65.80 = 28.30 : x
  2. Step 2: Convert to fraction form
    47.70/65.80 = 28.30/x
  3. Step 3: Cross multiply
    47.70x = 65.80 × 28.30
  4. Step 4: Simplify right side
    47.70x = 1,862.14
  5. Step 5: Solve for x
    x = 1,862.14/47.70
  6. Step 6: Final answer
    x = 39.04

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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.