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Finding the Fourth Proportional to 6.90, 10.35 and 2.09

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Solution

The fourth proportional to 6.90, 10.35 and 2.09 is: 3.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.90 : 10.35 = 2.09 : x
  2. Step 2: Convert to fraction form
    6.90/10.35 = 2.09/x
  3. Step 3: Cross multiply
    6.90x = 10.35 × 2.09
  4. Step 4: Simplify right side
    6.90x = 21.58
  5. Step 5: Solve for x
    x = 21.58/6.90
  6. Step 6: Final answer
    x = 3.13

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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.