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Finding the Fourth Proportional to 619.68, 929.42 and 208.72

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Solution

The fourth proportional to 619.68, 929.42 and 208.72 is: 313.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.68 : 929.42 = 208.72 : x
  2. Step 2: Convert to fraction form
    619.68/929.42 = 208.72/x
  3. Step 3: Cross multiply
    619.68x = 929.42 × 208.72
  4. Step 4: Simplify right side
    619.68x = 193,988.54
  5. Step 5: Solve for x
    x = 193,988.54/619.68
  6. Step 6: Final answer
    x = 313.05

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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.