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Finding the Fourth Proportional to 42.39, 58.39 and 40.57

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Solution

The fourth proportional to 42.39, 58.39 and 40.57 is: 55.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.39 : 58.39 = 40.57 : x
  2. Step 2: Convert to fraction form
    42.39/58.39 = 40.57/x
  3. Step 3: Cross multiply
    42.39x = 58.39 × 40.57
  4. Step 4: Simplify right side
    42.39x = 2,368.63
  5. Step 5: Solve for x
    x = 2,368.63/42.39
  6. Step 6: Final answer
    x = 55.88

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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.