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Finding the Fourth Proportional to 6.87, 10.31 and 6.51

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Solution

The fourth proportional to 6.87, 10.31 and 6.51 is: 9.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.87 : 10.31 = 6.51 : x
  2. Step 2: Convert to fraction form
    6.87/10.31 = 6.51/x
  3. Step 3: Cross multiply
    6.87x = 10.31 × 6.51
  4. Step 4: Simplify right side
    6.87x = 67.09
  5. Step 5: Solve for x
    x = 67.09/6.87
  6. Step 6: Final answer
    x = 9.77

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.