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Finding the Fourth Proportional to 655.04, 982.20 and 642.80

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Solution

The fourth proportional to 655.04, 982.20 and 642.80 is: 963.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.04 : 982.20 = 642.80 : x
  2. Step 2: Convert to fraction form
    655.04/982.20 = 642.80/x
  3. Step 3: Cross multiply
    655.04x = 982.20 × 642.80
  4. Step 4: Simplify right side
    655.04x = 631,358.16
  5. Step 5: Solve for x
    x = 631,358.16/655.04
  6. Step 6: Final answer
    x = 963.85

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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.