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Finding the Fourth Proportional to 205.13, 307.40 and 139.25

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Solution

The fourth proportional to 205.13, 307.40 and 139.25 is: 208.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.13 : 307.40 = 139.25 : x
  2. Step 2: Convert to fraction form
    205.13/307.40 = 139.25/x
  3. Step 3: Cross multiply
    205.13x = 307.40 × 139.25
  4. Step 4: Simplify right side
    205.13x = 42,805.52
  5. Step 5: Solve for x
    x = 42,805.52/205.13
  6. Step 6: Final answer
    x = 208.67

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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.