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Finding the Fourth Proportional to 619.75, 929.68 and 208.78

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Solution

The fourth proportional to 619.75, 929.68 and 208.78 is: 313.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.75 : 929.68 = 208.78 : x
  2. Step 2: Convert to fraction form
    619.75/929.68 = 208.78/x
  3. Step 3: Cross multiply
    619.75x = 929.68 × 208.78
  4. Step 4: Simplify right side
    619.75x = 194,095.74
  5. Step 5: Solve for x
    x = 194,095.74/619.75
  6. Step 6: Final answer
    x = 313.18

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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.