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Finding the Fourth Proportional to 6.21, 8.56 and 4.05

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Solution

The fourth proportional to 6.21, 8.56 and 4.05 is: 5.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    6.21 : 8.56 = 4.05 : x
  2. Step 2: Convert to fraction form
    6.21/8.56 = 4.05/x
  3. Step 3: Cross multiply
    6.21x = 8.56 × 4.05
  4. Step 4: Simplify right side
    6.21x = 34.67
  5. Step 5: Solve for x
    x = 34.67/6.21
  6. Step 6: Final answer
    x = 5.58

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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.