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Finding the Fourth Proportional to 45.20, 62.30 and 39.40

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Solution

The fourth proportional to 45.20, 62.30 and 39.40 is: 54.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    45.20 : 62.30 = 39.40 : x
  2. Step 2: Convert to fraction form
    45.20/62.30 = 39.40/x
  3. Step 3: Cross multiply
    45.20x = 62.30 × 39.40
  4. Step 4: Simplify right side
    45.20x = 2,454.62
  5. Step 5: Solve for x
    x = 2,454.62/45.20
  6. Step 6: Final answer
    x = 54.31

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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.