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Finding the Fourth Proportional to 42.40, 62.78 and 42.40

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Solution

The fourth proportional to 42.40, 62.78 and 42.40 is: 62.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    42.40 : 62.78 = 42.40 : x
  2. Step 2: Convert to fraction form
    42.40/62.78 = 42.40/x
  3. Step 3: Cross multiply
    42.40x = 62.78 × 42.40
  4. Step 4: Simplify right side
    42.40x = 2,661.87
  5. Step 5: Solve for x
    x = 2,661.87/42.40
  6. Step 6: Final answer
    x = 62.78

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.