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Finding the Fourth Proportional to 51.62, 71.31 and 39.40

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Solution

The fourth proportional to 51.62, 71.31 and 39.40 is: 54.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.62 : 71.31 = 39.40 : x
  2. Step 2: Convert to fraction form
    51.62/71.31 = 39.40/x
  3. Step 3: Cross multiply
    51.62x = 71.31 × 39.40
  4. Step 4: Simplify right side
    51.62x = 2,809.58
  5. Step 5: Solve for x
    x = 2,809.58/51.62
  6. Step 6: Final answer
    x = 54.43

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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.