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Finding the Fourth Proportional to 71.22, 98.28 and 42.12

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Solution

The fourth proportional to 71.22, 98.28 and 42.12 is: 58.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.22 : 98.28 = 42.12 : x
  2. Step 2: Convert to fraction form
    71.22/98.28 = 42.12/x
  3. Step 3: Cross multiply
    71.22x = 98.28 × 42.12
  4. Step 4: Simplify right side
    71.22x = 4,139.55
  5. Step 5: Solve for x
    x = 4,139.55/71.22
  6. Step 6: Final answer
    x = 58.12

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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.