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Finding the Fourth Proportional to 71.02, 106.62 and 65.80

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Solution

The fourth proportional to 71.02, 106.62 and 65.80 is: 98.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.02 : 106.62 = 65.80 : x
  2. Step 2: Convert to fraction form
    71.02/106.62 = 65.80/x
  3. Step 3: Cross multiply
    71.02x = 106.62 × 65.80
  4. Step 4: Simplify right side
    71.02x = 7,015.60
  5. Step 5: Solve for x
    x = 7,015.60/71.02
  6. Step 6: Final answer
    x = 98.78

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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.