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Finding the Fourth Proportional to 661.20, 990.48 and 499.04

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Solution

The fourth proportional to 661.20, 990.48 and 499.04 is: 747.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.20 : 990.48 = 499.04 : x
  2. Step 2: Convert to fraction form
    661.20/990.48 = 499.04/x
  3. Step 3: Cross multiply
    661.20x = 990.48 × 499.04
  4. Step 4: Simplify right side
    661.20x = 494,289.14
  5. Step 5: Solve for x
    x = 494,289.14/661.20
  6. Step 6: Final answer
    x = 747.56

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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.