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Finding the Fourth Proportional to 489.86, 675.80 and 290.66

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Solution

The fourth proportional to 489.86, 675.80 and 290.66 is: 400.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.86 : 675.80 = 290.66 : x
  2. Step 2: Convert to fraction form
    489.86/675.80 = 290.66/x
  3. Step 3: Cross multiply
    489.86x = 675.80 × 290.66
  4. Step 4: Simplify right side
    489.86x = 196,428.03
  5. Step 5: Solve for x
    x = 196,428.03/489.86
  6. Step 6: Final answer
    x = 400.99

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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.