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Finding the Fourth Proportional to 71.17, 98.21 and 42.05

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Solution

The fourth proportional to 71.17, 98.21 and 42.05 is: 58.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.17 : 98.21 = 42.05 : x
  2. Step 2: Convert to fraction form
    71.17/98.21 = 42.05/x
  3. Step 3: Cross multiply
    71.17x = 98.21 × 42.05
  4. Step 4: Simplify right side
    71.17x = 4,130.08
  5. Step 5: Solve for x
    x = 4,130.08/71.17
  6. Step 6: Final answer
    x = 58.03

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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.