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Finding the Fourth Proportional to 521.69, 780.66 and 490.55

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Solution

The fourth proportional to 521.69, 780.66 and 490.55 is: 734.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.69 : 780.66 = 490.55 : x
  2. Step 2: Convert to fraction form
    521.69/780.66 = 490.55/x
  3. Step 3: Cross multiply
    521.69x = 780.66 × 490.55
  4. Step 4: Simplify right side
    521.69x = 382,948.86
  5. Step 5: Solve for x
    x = 382,948.86/521.69
  6. Step 6: Final answer
    x = 734.06

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.