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Finding the Fourth Proportional to 85.34, 127.28 and 76.23

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Solution

The fourth proportional to 85.34, 127.28 and 76.23 is: 113.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.34 : 127.28 = 76.23 : x
  2. Step 2: Convert to fraction form
    85.34/127.28 = 76.23/x
  3. Step 3: Cross multiply
    85.34x = 127.28 × 76.23
  4. Step 4: Simplify right side
    85.34x = 9,702.17
  5. Step 5: Solve for x
    x = 9,702.17/85.34
  6. Step 6: Final answer
    x = 113.70

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.