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Finding the Fourth Proportional to 412.99, 619.49 and 139.10

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Solution

The fourth proportional to 412.99, 619.49 and 139.10 is: 208.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.99 : 619.49 = 139.10 : x
  2. Step 2: Convert to fraction form
    412.99/619.49 = 139.10/x
  3. Step 3: Cross multiply
    412.99x = 619.49 × 139.10
  4. Step 4: Simplify right side
    412.99x = 86,171.06
  5. Step 5: Solve for x
    x = 86,171.06/412.99
  6. Step 6: Final answer
    x = 208.65

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Double scale
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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.