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Finding the Fourth Proportional to 63.62, 87.72 and 56.78

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Solution

The fourth proportional to 63.62, 87.72 and 56.78 is: 78.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    63.62 : 87.72 = 56.78 : x
  2. Step 2: Convert to fraction form
    63.62/87.72 = 56.78/x
  3. Step 3: Cross multiply
    63.62x = 87.72 × 56.78
  4. Step 4: Simplify right side
    63.62x = 4,980.74
  5. Step 5: Solve for x
    x = 4,980.74/63.62
  6. Step 6: Final answer
    x = 78.29

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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.