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Finding the Fourth Proportional to 489.66, 675.60 and 279.81

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Solution

The fourth proportional to 489.66, 675.60 and 279.81 is: 386.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.66 : 675.60 = 279.81 : x
  2. Step 2: Convert to fraction form
    489.66/675.60 = 279.81/x
  3. Step 3: Cross multiply
    489.66x = 675.60 × 279.81
  4. Step 4: Simplify right side
    489.66x = 189,039.64
  5. Step 5: Solve for x
    x = 189,039.64/489.66
  6. Step 6: Final answer
    x = 386.06

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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.