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Finding the Fourth Proportional to 654.72, 980.79 and 394.79

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Solution

The fourth proportional to 654.72, 980.79 and 394.79 is: 591.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.72 : 980.79 = 394.79 : x
  2. Step 2: Convert to fraction form
    654.72/980.79 = 394.79/x
  3. Step 3: Cross multiply
    654.72x = 980.79 × 394.79
  4. Step 4: Simplify right side
    654.72x = 387,206.56
  5. Step 5: Solve for x
    x = 387,206.56/654.72
  6. Step 6: Final answer
    x = 591.41

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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.