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Finding the Fourth Proportional to 69.10, 103.12 and 57.10

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Solution

The fourth proportional to 69.10, 103.12 and 57.10 is: 85.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    69.10 : 103.12 = 57.10 : x
  2. Step 2: Convert to fraction form
    69.10/103.12 = 57.10/x
  3. Step 3: Cross multiply
    69.10x = 103.12 × 57.10
  4. Step 4: Simplify right side
    69.10x = 5,888.15
  5. Step 5: Solve for x
    x = 5,888.15/69.10
  6. Step 6: Final answer
    x = 85.21

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.