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Finding the Fourth Proportional to 10.15, 15.21 and 3.72

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Solution

The fourth proportional to 10.15, 15.21 and 3.72 is: 5.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    10.15 : 15.21 = 3.72 : x
  2. Step 2: Convert to fraction form
    10.15/15.21 = 3.72/x
  3. Step 3: Cross multiply
    10.15x = 15.21 × 3.72
  4. Step 4: Simplify right side
    10.15x = 56.65
  5. Step 5: Solve for x
    x = 56.65/10.15
  6. Step 6: Final answer
    x = 5.58

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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.