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Finding the Fourth Proportional to 103.60, 155.30 and 42.70

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Solution

The fourth proportional to 103.60, 155.30 and 42.70 is: 64.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.60 : 155.30 = 42.70 : x
  2. Step 2: Convert to fraction form
    103.60/155.30 = 42.70/x
  3. Step 3: Cross multiply
    103.60x = 155.30 × 42.70
  4. Step 4: Simplify right side
    103.60x = 6,631.31
  5. Step 5: Solve for x
    x = 6,631.31/103.60
  6. Step 6: Final answer
    x = 64.01

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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.