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Finding the Fourth Proportional to 75.15, 103.69 and 42.39

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Solution

The fourth proportional to 75.15, 103.69 and 42.39 is: 58.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    75.15 : 103.69 = 42.39 : x
  2. Step 2: Convert to fraction form
    75.15/103.69 = 42.39/x
  3. Step 3: Cross multiply
    75.15x = 103.69 × 42.39
  4. Step 4: Simplify right side
    75.15x = 4,395.05
  5. Step 5: Solve for x
    x = 4,395.05/75.15
  6. Step 6: Final answer
    x = 58.49

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.