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Finding the Fourth Proportional to 20, 29.86 and 18.56

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Solution

The fourth proportional to 20, 29.86 and 18.56 is: 27.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    20 : 29.86 = 18.56 : x
  2. Step 2: Convert to fraction form
    20/29.86 = 18.56/x
  3. Step 3: Cross multiply
    20x = 29.86 × 18.56
  4. Step 4: Simplify right side
    20x = 554.20
  5. Step 5: Solve for x
    x = 554.20/20
  6. Step 6: Final answer
    x = 27.71

Related Problems

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Double scale
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Similar ratio
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.