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Finding the Fourth Proportional to 120.20, 180.28 and 39.02

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Solution

The fourth proportional to 120.20, 180.28 and 39.02 is: 58.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    120.20 : 180.28 = 39.02 : x
  2. Step 2: Convert to fraction form
    120.20/180.28 = 39.02/x
  3. Step 3: Cross multiply
    120.20x = 180.28 × 39.02
  4. Step 4: Simplify right side
    120.20x = 7,034.53
  5. Step 5: Solve for x
    x = 7,034.53/120.20
  6. Step 6: Final answer
    x = 58.52

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1.5x scale

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.