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Finding the Fourth Proportional to 155.17, 213.78 and 145.09

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Solution

The fourth proportional to 155.17, 213.78 and 145.09 is: 199.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.17 : 213.78 = 145.09 : x
  2. Step 2: Convert to fraction form
    155.17/213.78 = 145.09/x
  3. Step 3: Cross multiply
    155.17x = 213.78 × 145.09
  4. Step 4: Simplify right side
    155.17x = 31,017.34
  5. Step 5: Solve for x
    x = 31,017.34/155.17
  6. Step 6: Final answer
    x = 199.89

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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.