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Finding the Fourth Proportional to 51.87, 71.70 and 39.09

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Solution

The fourth proportional to 51.87, 71.70 and 39.09 is: 54.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    51.87 : 71.70 = 39.09 : x
  2. Step 2: Convert to fraction form
    51.87/71.70 = 39.09/x
  3. Step 3: Cross multiply
    51.87x = 71.70 × 39.09
  4. Step 4: Simplify right side
    51.87x = 2,802.75
  5. Step 5: Solve for x
    x = 2,802.75/51.87
  6. Step 6: Final answer
    x = 54.03

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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.