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Finding the Fourth Proportional to 67.40, 100.38 and 66.84

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Solution

The fourth proportional to 67.40, 100.38 and 66.84 is: 99.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    67.40 : 100.38 = 66.84 : x
  2. Step 2: Convert to fraction form
    67.40/100.38 = 66.84/x
  3. Step 3: Cross multiply
    67.40x = 100.38 × 66.84
  4. Step 4: Simplify right side
    67.40x = 6,709.40
  5. Step 5: Solve for x
    x = 6,709.40/67.40
  6. Step 6: Final answer
    x = 99.55

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.