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Finding the Fourth Proportional to 654.40, 979.80 and 491.50

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Solution

The fourth proportional to 654.40, 979.80 and 491.50 is: 735.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.40 : 979.80 = 491.50 : x
  2. Step 2: Convert to fraction form
    654.40/979.80 = 491.50/x
  3. Step 3: Cross multiply
    654.40x = 979.80 × 491.50
  4. Step 4: Simplify right side
    654.40x = 481,571.70
  5. Step 5: Solve for x
    x = 481,571.70/654.40
  6. Step 6: Final answer
    x = 735.90

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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.