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Finding the Fourth Proportional to 489.40, 675.26 and 279.54

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Solution

The fourth proportional to 489.40, 675.26 and 279.54 is: 385.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.40 : 675.26 = 279.54 : x
  2. Step 2: Convert to fraction form
    489.40/675.26 = 279.54/x
  3. Step 3: Cross multiply
    489.40x = 675.26 × 279.54
  4. Step 4: Simplify right side
    489.40x = 188,762.18
  5. Step 5: Solve for x
    x = 188,762.18/489.40
  6. Step 6: Final answer
    x = 385.70

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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.