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Finding the Fourth Proportional to 125.72, 188.90 and 71.65

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Solution

The fourth proportional to 125.72, 188.90 and 71.65 is: 107.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    125.72 : 188.90 = 71.65 : x
  2. Step 2: Convert to fraction form
    125.72/188.90 = 71.65/x
  3. Step 3: Cross multiply
    125.72x = 188.90 × 71.65
  4. Step 4: Simplify right side
    125.72x = 13,533.38
  5. Step 5: Solve for x
    x = 13,533.38/125.72
  6. Step 6: Final answer
    x = 107.65

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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.