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Finding the Fourth Proportional to 56.84, 85.26 and 20.79

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Solution

The fourth proportional to 56.84, 85.26 and 20.79 is: 31.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    56.84 : 85.26 = 20.79 : x
  2. Step 2: Convert to fraction form
    56.84/85.26 = 20.79/x
  3. Step 3: Cross multiply
    56.84x = 85.26 × 20.79
  4. Step 4: Simplify right side
    56.84x = 1,772.56
  5. Step 5: Solve for x
    x = 1,772.56/56.84
  6. Step 6: Final answer
    x = 31.19

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.