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Finding the Fourth Proportional to 145.31, 200.42 and 87.09

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Solution

The fourth proportional to 145.31, 200.42 and 87.09 is: 120.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.31 : 200.42 = 87.09 : x
  2. Step 2: Convert to fraction form
    145.31/200.42 = 87.09/x
  3. Step 3: Cross multiply
    145.31x = 200.42 × 87.09
  4. Step 4: Simplify right side
    145.31x = 17,454.14
  5. Step 5: Solve for x
    x = 17,454.14/145.31
  6. Step 6: Final answer
    x = 120.12

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.