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Finding the Fourth Proportional to 41.40, 61.80 and 38.70

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Solution

The fourth proportional to 41.40, 61.80 and 38.70 is: 57.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    41.40 : 61.80 = 38.70 : x
  2. Step 2: Convert to fraction form
    41.40/61.80 = 38.70/x
  3. Step 3: Cross multiply
    41.40x = 61.80 × 38.70
  4. Step 4: Simplify right side
    41.40x = 2,391.66
  5. Step 5: Solve for x
    x = 2,391.66/41.40
  6. Step 6: Final answer
    x = 57.77

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.