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Finding the Fourth Proportional to 63.40, 87.78 and 58.60

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Solution

The fourth proportional to 63.40, 87.78 and 58.60 is: 81.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    63.40 : 87.78 = 58.60 : x
  2. Step 2: Convert to fraction form
    63.40/87.78 = 58.60/x
  3. Step 3: Cross multiply
    63.40x = 87.78 × 58.60
  4. Step 4: Simplify right side
    63.40x = 5,143.91
  5. Step 5: Solve for x
    x = 5,143.91/63.40
  6. Step 6: Final answer
    x = 81.13

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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.