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Finding the Fourth Proportional to 14.21, 21.29 and 5.18

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Solution

The fourth proportional to 14.21, 21.29 and 5.18 is: 7.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    14.21 : 21.29 = 5.18 : x
  2. Step 2: Convert to fraction form
    14.21/21.29 = 5.18/x
  3. Step 3: Cross multiply
    14.21x = 21.29 × 5.18
  4. Step 4: Simplify right side
    14.21x = 110.15
  5. Step 5: Solve for x
    x = 110.15/14.21
  6. Step 6: Final answer
    x = 7.75

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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.