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Finding the Fourth Proportional to 489.09, 675 and 312.06

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Solution

The fourth proportional to 489.09, 675 and 312.06 is: 430.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.09 : 675 = 312.06 : x
  2. Step 2: Convert to fraction form
    489.09/675 = 312.06/x
  3. Step 3: Cross multiply
    489.09x = 675 × 312.06
  4. Step 4: Simplify right side
    489.09x = 210,640.50
  5. Step 5: Solve for x
    x = 210,640.50/489.09
  6. Step 6: Final answer
    x = 430.68

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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.