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Finding the Fourth Proportional to 661.95, 990.59 and 488.21

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Solution

The fourth proportional to 661.95, 990.59 and 488.21 is: 730.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.95 : 990.59 = 488.21 : x
  2. Step 2: Convert to fraction form
    661.95/990.59 = 488.21/x
  3. Step 3: Cross multiply
    661.95x = 990.59 × 488.21
  4. Step 4: Simplify right side
    661.95x = 483,608.55
  5. Step 5: Solve for x
    x = 483,608.55/661.95
  6. Step 6: Final answer
    x = 730.58

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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.