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Finding the Fourth Proportional to 20, 29.76 and 18.64

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Solution

The fourth proportional to 20, 29.76 and 18.64 is: 27.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    20 : 29.76 = 18.64 : x
  2. Step 2: Convert to fraction form
    20/29.76 = 18.64/x
  3. Step 3: Cross multiply
    20x = 29.76 × 18.64
  4. Step 4: Simplify right side
    20x = 554.73
  5. Step 5: Solve for x
    x = 554.73/20
  6. Step 6: Final answer
    x = 27.74

Related Problems

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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.