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Finding the Fourth Proportional to 30.70, 42.33 and 30.12

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Solution

The fourth proportional to 30.70, 42.33 and 30.12 is: 41.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.70 : 42.33 = 30.12 : x
  2. Step 2: Convert to fraction form
    30.70/42.33 = 30.12/x
  3. Step 3: Cross multiply
    30.70x = 42.33 × 30.12
  4. Step 4: Simplify right side
    30.70x = 1,274.98
  5. Step 5: Solve for x
    x = 1,274.98/30.70
  6. Step 6: Final answer
    x = 41.53

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.