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Finding the Fourth Proportional to 3.05, 4.21 and 1.68

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Solution

The fourth proportional to 3.05, 4.21 and 1.68 is: 2.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    3.05 : 4.21 = 1.68 : x
  2. Step 2: Convert to fraction form
    3.05/4.21 = 1.68/x
  3. Step 3: Cross multiply
    3.05x = 4.21 × 1.68
  4. Step 4: Simplify right side
    3.05x = 7.08
  5. Step 5: Solve for x
    x = 7.08/3.05
  6. Step 6: Final answer
    x = 2.32

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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.