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Finding the Fourth Proportional to 67.60, 101.40 and 65.78

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Solution

The fourth proportional to 67.60, 101.40 and 65.78 is: 98.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    67.60 : 101.40 = 65.78 : x
  2. Step 2: Convert to fraction form
    67.60/101.40 = 65.78/x
  3. Step 3: Cross multiply
    67.60x = 101.40 × 65.78
  4. Step 4: Simplify right side
    67.60x = 6,669.34
  5. Step 5: Solve for x
    x = 6,669.34/67.60
  6. Step 6: Final answer
    x = 98.66

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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.