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Finding the Fourth Proportional to 521.40, 780.66 and 264.36

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Solution

The fourth proportional to 521.40, 780.66 and 264.36 is: 395.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.40 : 780.66 = 264.36 : x
  2. Step 2: Convert to fraction form
    521.40/780.66 = 264.36/x
  3. Step 3: Cross multiply
    521.40x = 780.66 × 264.36
  4. Step 4: Simplify right side
    521.40x = 206,375.28
  5. Step 5: Solve for x
    x = 206,375.28/521.40
  6. Step 6: Final answer
    x = 395.81

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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.