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Finding the Fourth Proportional to 145.88, 218.82 and 80.78

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Solution

The fourth proportional to 145.88, 218.82 and 80.78 is: 121.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.88 : 218.82 = 80.78 : x
  2. Step 2: Convert to fraction form
    145.88/218.82 = 80.78/x
  3. Step 3: Cross multiply
    145.88x = 218.82 × 80.78
  4. Step 4: Simplify right side
    145.88x = 17,676.28
  5. Step 5: Solve for x
    x = 17,676.28/145.88
  6. Step 6: Final answer
    x = 121.17

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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.