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Finding the Fourth Proportional to 85.75, 118.35 and 56.71

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Solution

The fourth proportional to 85.75, 118.35 and 56.71 is: 78.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.75 : 118.35 = 56.71 : x
  2. Step 2: Convert to fraction form
    85.75/118.35 = 56.71/x
  3. Step 3: Cross multiply
    85.75x = 118.35 × 56.71
  4. Step 4: Simplify right side
    85.75x = 6,711.63
  5. Step 5: Solve for x
    x = 6,711.63/85.75
  6. Step 6: Final answer
    x = 78.27

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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.