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Finding the Fourth Proportional to 63.45, 87.51 and 42.70

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Solution

The fourth proportional to 63.45, 87.51 and 42.70 is: 58.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    63.45 : 87.51 = 42.70 : x
  2. Step 2: Convert to fraction form
    63.45/87.51 = 42.70/x
  3. Step 3: Cross multiply
    63.45x = 87.51 × 42.70
  4. Step 4: Simplify right side
    63.45x = 3,736.68
  5. Step 5: Solve for x
    x = 3,736.68/63.45
  6. Step 6: Final answer
    x = 58.89

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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.