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Finding the Fourth Proportional to 145.45, 218.25 and 80.50

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Solution

The fourth proportional to 145.45, 218.25 and 80.50 is: 120.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.45 : 218.25 = 80.50 : x
  2. Step 2: Convert to fraction form
    145.45/218.25 = 80.50/x
  3. Step 3: Cross multiply
    145.45x = 218.25 × 80.50
  4. Step 4: Simplify right side
    145.45x = 17,569.13
  5. Step 5: Solve for x
    x = 17,569.13/145.45
  6. Step 6: Final answer
    x = 120.79

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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.