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Finding the Fourth Proportional to 42.34, 63.54 and 28.78

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Solution

The fourth proportional to 42.34, 63.54 and 28.78 is: 43.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.34 : 63.54 = 28.78 : x
  2. Step 2: Convert to fraction form
    42.34/63.54 = 28.78/x
  3. Step 3: Cross multiply
    42.34x = 63.54 × 28.78
  4. Step 4: Simplify right side
    42.34x = 1,828.68
  5. Step 5: Solve for x
    x = 1,828.68/42.34
  6. Step 6: Final answer
    x = 43.19

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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.