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Finding the Fourth Proportional to 71.58, 98.78 and 42.47

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Solution

The fourth proportional to 71.58, 98.78 and 42.47 is: 58.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.58 : 98.78 = 42.47 : x
  2. Step 2: Convert to fraction form
    71.58/98.78 = 42.47/x
  3. Step 3: Cross multiply
    71.58x = 98.78 × 42.47
  4. Step 4: Simplify right side
    71.58x = 4,195.09
  5. Step 5: Solve for x
    x = 4,195.09/71.58
  6. Step 6: Final answer
    x = 58.61

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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.