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Finding the Fourth Proportional to 29.70, 39.18 and 29.70

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Solution

The fourth proportional to 29.70, 39.18 and 29.70 is: 39.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    29.70 : 39.18 = 29.70 : x
  2. Step 2: Convert to fraction form
    29.70/39.18 = 29.70/x
  3. Step 3: Cross multiply
    29.70x = 39.18 × 29.70
  4. Step 4: Simplify right side
    29.70x = 1,163.65
  5. Step 5: Solve for x
    x = 1,163.65/29.70
  6. Step 6: Final answer
    x = 39.18

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Why These Related Problems?

These problems maintain the same ratio (1.32) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.