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Finding the Fourth Proportional to 83.89, 125.70 and 65.80

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Solution

The fourth proportional to 83.89, 125.70 and 65.80 is: 98.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.89 : 125.70 = 65.80 : x
  2. Step 2: Convert to fraction form
    83.89/125.70 = 65.80/x
  3. Step 3: Cross multiply
    83.89x = 125.70 × 65.80
  4. Step 4: Simplify right side
    83.89x = 8,271.06
  5. Step 5: Solve for x
    x = 8,271.06/83.89
  6. Step 6: Final answer
    x = 98.59

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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.