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Finding the Fourth Proportional to 5.22, 7.21 and 4.15

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Solution

The fourth proportional to 5.22, 7.21 and 4.15 is: 5.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    5.22 : 7.21 = 4.15 : x
  2. Step 2: Convert to fraction form
    5.22/7.21 = 4.15/x
  3. Step 3: Cross multiply
    5.22x = 7.21 × 4.15
  4. Step 4: Simplify right side
    5.22x = 29.86
  5. Step 5: Solve for x
    x = 29.86/5.22
  6. Step 6: Final answer
    x = 5.72

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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.