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Finding the Fourth Proportional to 145.45, 217.87 and 87.49

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Solution

The fourth proportional to 145.45, 217.87 and 87.49 is: 131.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.45 : 217.87 = 87.49 : x
  2. Step 2: Convert to fraction form
    145.45/217.87 = 87.49/x
  3. Step 3: Cross multiply
    145.45x = 217.87 × 87.49
  4. Step 4: Simplify right side
    145.45x = 19,061.45
  5. Step 5: Solve for x
    x = 19,061.45/145.45
  6. Step 6: Final answer
    x = 131.05

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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.