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Finding the Fourth Proportional to 30.79, 42.07 and 30.59

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Solution

The fourth proportional to 30.79, 42.07 and 30.59 is: 41.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.79 : 42.07 = 30.59 : x
  2. Step 2: Convert to fraction form
    30.79/42.07 = 30.59/x
  3. Step 3: Cross multiply
    30.79x = 42.07 × 30.59
  4. Step 4: Simplify right side
    30.79x = 1,286.63
  5. Step 5: Solve for x
    x = 1,286.63/30.79
  6. Step 6: Final answer
    x = 41.79

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.