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Finding the Fourth Proportional to 85.66, 118.26 and 56.57

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Solution

The fourth proportional to 85.66, 118.26 and 56.57 is: 78.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.66 : 118.26 = 56.57 : x
  2. Step 2: Convert to fraction form
    85.66/118.26 = 56.57/x
  3. Step 3: Cross multiply
    85.66x = 118.26 × 56.57
  4. Step 4: Simplify right side
    85.66x = 6,689.38
  5. Step 5: Solve for x
    x = 6,689.38/85.66
  6. Step 6: Final answer
    x = 78.09

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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.