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Finding the Fourth Proportional to 66.88, 100.32 and 28.38

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Solution

The fourth proportional to 66.88, 100.32 and 28.38 is: 42.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.88 : 100.32 = 28.38 : x
  2. Step 2: Convert to fraction form
    66.88/100.32 = 28.38/x
  3. Step 3: Cross multiply
    66.88x = 100.32 × 28.38
  4. Step 4: Simplify right side
    66.88x = 2,847.08
  5. Step 5: Solve for x
    x = 2,847.08/66.88
  6. Step 6: Final answer
    x = 42.57

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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.