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Finding the Fourth Proportional to 4.21, 6.29 and 3.20

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Solution

The fourth proportional to 4.21, 6.29 and 3.20 is: 4.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    4.21 : 6.29 = 3.20 : x
  2. Step 2: Convert to fraction form
    4.21/6.29 = 3.20/x
  3. Step 3: Cross multiply
    4.21x = 6.29 × 3.20
  4. Step 4: Simplify right side
    4.21x = 20.13
  5. Step 5: Solve for x
    x = 20.13/4.21
  6. Step 6: Final answer
    x = 4.78

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.