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Finding the Fourth Proportional to 619.85, 929.78 and 208.99

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Solution

The fourth proportional to 619.85, 929.78 and 208.99 is: 313.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.85 : 929.78 = 208.99 : x
  2. Step 2: Convert to fraction form
    619.85/929.78 = 208.99/x
  3. Step 3: Cross multiply
    619.85x = 929.78 × 208.99
  4. Step 4: Simplify right side
    619.85x = 194,317.59
  5. Step 5: Solve for x
    x = 194,317.59/619.85
  6. Step 6: Final answer
    x = 313.49

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Similar ratio
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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.