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Finding the Fourth Proportional to 521.20, 780.54 and 497.80

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Solution

The fourth proportional to 521.20, 780.54 and 497.80 is: 745.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.20 : 780.54 = 497.80 : x
  2. Step 2: Convert to fraction form
    521.20/780.54 = 497.80/x
  3. Step 3: Cross multiply
    521.20x = 780.54 × 497.80
  4. Step 4: Simplify right side
    521.20x = 388,552.81
  5. Step 5: Solve for x
    x = 388,552.81/521.20
  6. Step 6: Final answer
    x = 745.50

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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.