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Finding the Fourth Proportional to 9.15, 12.70 and 8.75

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Solution

The fourth proportional to 9.15, 12.70 and 8.75 is: 12.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    9.15 : 12.70 = 8.75 : x
  2. Step 2: Convert to fraction form
    9.15/12.70 = 8.75/x
  3. Step 3: Cross multiply
    9.15x = 12.70 × 8.75
  4. Step 4: Simplify right side
    9.15x = 111.08
  5. Step 5: Solve for x
    x = 111.08/9.15
  6. Step 6: Final answer
    x = 12.14

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.