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Finding the Fourth Proportional to 42.40, 63.58 and 18.38

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Solution

The fourth proportional to 42.40, 63.58 and 18.38 is: 27.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.40 : 63.58 = 18.38 : x
  2. Step 2: Convert to fraction form
    42.40/63.58 = 18.38/x
  3. Step 3: Cross multiply
    42.40x = 63.58 × 18.38
  4. Step 4: Simplify right side
    42.40x = 1,168.60
  5. Step 5: Solve for x
    x = 1,168.60/42.40
  6. Step 6: Final answer
    x = 27.56

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.