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Finding the Fourth Proportional to 8.12, 12.15 and 4.75

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Solution

The fourth proportional to 8.12, 12.15 and 4.75 is: 7.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    8.12 : 12.15 = 4.75 : x
  2. Step 2: Convert to fraction form
    8.12/12.15 = 4.75/x
  3. Step 3: Cross multiply
    8.12x = 12.15 × 4.75
  4. Step 4: Simplify right side
    8.12x = 57.66
  5. Step 5: Solve for x
    x = 57.66/8.12
  6. Step 6: Final answer
    x = 7.10

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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.