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Finding the Fourth Proportional to 30.61, 45.81 and 28.65

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Solution

The fourth proportional to 30.61, 45.81 and 28.65 is: 42.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.61 : 45.81 = 28.65 : x
  2. Step 2: Convert to fraction form
    30.61/45.81 = 28.65/x
  3. Step 3: Cross multiply
    30.61x = 45.81 × 28.65
  4. Step 4: Simplify right side
    30.61x = 1,312.46
  5. Step 5: Solve for x
    x = 1,312.46/30.61
  6. Step 6: Final answer
    x = 42.88

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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.