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Finding the Fourth Proportional to 101.30, 138.55 and 99.71

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Solution

The fourth proportional to 101.30, 138.55 and 99.71 is: 136.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.30 : 138.55 = 99.71 : x
  2. Step 2: Convert to fraction form
    101.30/138.55 = 99.71/x
  3. Step 3: Cross multiply
    101.30x = 138.55 × 99.71
  4. Step 4: Simplify right side
    101.30x = 13,814.13
  5. Step 5: Solve for x
    x = 13,814.13/101.30
  6. Step 6: Final answer
    x = 136.38

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.