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Finding the Fourth Proportional to 30.67, 42.53 and 28.85

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Solution

The fourth proportional to 30.67, 42.53 and 28.85 is: 40.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.67 : 42.53 = 28.85 : x
  2. Step 2: Convert to fraction form
    30.67/42.53 = 28.85/x
  3. Step 3: Cross multiply
    30.67x = 42.53 × 28.85
  4. Step 4: Simplify right side
    30.67x = 1,226.63
  5. Step 5: Solve for x
    x = 1,226.63/30.67
  6. Step 6: Final answer
    x = 40.00

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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.