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Finding the Fourth Proportional to 520.36, 780.88 and 486.21

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Solution

The fourth proportional to 520.36, 780.88 and 486.21 is: 729.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.36 : 780.88 = 486.21 : x
  2. Step 2: Convert to fraction form
    520.36/780.88 = 486.21/x
  3. Step 3: Cross multiply
    520.36x = 780.88 × 486.21
  4. Step 4: Simplify right side
    520.36x = 379,671.66
  5. Step 5: Solve for x
    x = 379,671.66/520.36
  6. Step 6: Final answer
    x = 729.63

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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.