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Finding the Fourth Proportional to 84.60, 127.05 and 61.80

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Solution

The fourth proportional to 84.60, 127.05 and 61.80 is: 92.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.60 : 127.05 = 61.80 : x
  2. Step 2: Convert to fraction form
    84.60/127.05 = 61.80/x
  3. Step 3: Cross multiply
    84.60x = 127.05 × 61.80
  4. Step 4: Simplify right side
    84.60x = 7,851.69
  5. Step 5: Solve for x
    x = 7,851.69/84.60
  6. Step 6: Final answer
    x = 92.81

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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.