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Finding the Fourth Proportional to 489.02, 670.18 and 488.20

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Solution

The fourth proportional to 489.02, 670.18 and 488.20 is: 669.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.02 : 670.18 = 488.20 : x
  2. Step 2: Convert to fraction form
    489.02/670.18 = 488.20/x
  3. Step 3: Cross multiply
    489.02x = 670.18 × 488.20
  4. Step 4: Simplify right side
    489.02x = 327,181.88
  5. Step 5: Solve for x
    x = 327,181.88/489.02
  6. Step 6: Final answer
    x = 669.06

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.