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Finding the Fourth Proportional to 83.80, 125.64 and 51.30

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Solution

The fourth proportional to 83.80, 125.64 and 51.30 is: 76.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.80 : 125.64 = 51.30 : x
  2. Step 2: Convert to fraction form
    83.80/125.64 = 51.30/x
  3. Step 3: Cross multiply
    83.80x = 125.64 × 51.30
  4. Step 4: Simplify right side
    83.80x = 6,445.33
  5. Step 5: Solve for x
    x = 6,445.33/83.80
  6. Step 6: Final answer
    x = 76.91

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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.