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Finding the Fourth Proportional to 489.66, 675.68 and 279.88

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Solution

The fourth proportional to 489.66, 675.68 and 279.88 is: 386.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.66 : 675.68 = 279.88 : x
  2. Step 2: Convert to fraction form
    489.66/675.68 = 279.88/x
  3. Step 3: Cross multiply
    489.66x = 675.68 × 279.88
  4. Step 4: Simplify right side
    489.66x = 189,109.32
  5. Step 5: Solve for x
    x = 189,109.32/489.66
  6. Step 6: Final answer
    x = 386.21

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.