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Finding the Fourth Proportional to 28.47, 42.65 and 18.30

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Solution

The fourth proportional to 28.47, 42.65 and 18.30 is: 27.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    28.47 : 42.65 = 18.30 : x
  2. Step 2: Convert to fraction form
    28.47/42.65 = 18.30/x
  3. Step 3: Cross multiply
    28.47x = 42.65 × 18.30
  4. Step 4: Simplify right side
    28.47x = 780.40
  5. Step 5: Solve for x
    x = 780.40/28.47
  6. Step 6: Final answer
    x = 27.41

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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.