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Finding the Fourth Proportional to 489.71, 675.77 and 279.85

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Solution

The fourth proportional to 489.71, 675.77 and 279.85 is: 386.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.71 : 675.77 = 279.85 : x
  2. Step 2: Convert to fraction form
    489.71/675.77 = 279.85/x
  3. Step 3: Cross multiply
    489.71x = 675.77 × 279.85
  4. Step 4: Simplify right side
    489.71x = 189,114.23
  5. Step 5: Solve for x
    x = 189,114.23/489.71
  6. Step 6: Final answer
    x = 386.18

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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.