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Finding the Fourth Proportional to 71.20, 98.20 and 42.06

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Solution

The fourth proportional to 71.20, 98.20 and 42.06 is: 58.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.20 : 98.20 = 42.06 : x
  2. Step 2: Convert to fraction form
    71.20/98.20 = 42.06/x
  3. Step 3: Cross multiply
    71.20x = 98.20 × 42.06
  4. Step 4: Simplify right side
    71.20x = 4,130.29
  5. Step 5: Solve for x
    x = 4,130.29/71.20
  6. Step 6: Final answer
    x = 58.01

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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.