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Finding the Fourth Proportional to 145.12, 217.59 and 80.15

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Solution

The fourth proportional to 145.12, 217.59 and 80.15 is: 120.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.12 : 217.59 = 80.15 : x
  2. Step 2: Convert to fraction form
    145.12/217.59 = 80.15/x
  3. Step 3: Cross multiply
    145.12x = 217.59 × 80.15
  4. Step 4: Simplify right side
    145.12x = 17,440.75
  5. Step 5: Solve for x
    x = 17,440.75/145.12
  6. Step 6: Final answer
    x = 120.18

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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.