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Finding the Fourth Proportional to 489.78, 675.54 and 342.18

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Solution

The fourth proportional to 489.78, 675.54 and 342.18 is: 471.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.78 : 675.54 = 342.18 : x
  2. Step 2: Convert to fraction form
    489.78/675.54 = 342.18/x
  3. Step 3: Cross multiply
    489.78x = 675.54 × 342.18
  4. Step 4: Simplify right side
    489.78x = 231,156.28
  5. Step 5: Solve for x
    x = 231,156.28/489.78
  6. Step 6: Final answer
    x = 471.96

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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.