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Finding the Fourth Proportional to 520.34, 780.78 and 479.04

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Solution

The fourth proportional to 520.34, 780.78 and 479.04 is: 718.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.34 : 780.78 = 479.04 : x
  2. Step 2: Convert to fraction form
    520.34/780.78 = 479.04/x
  3. Step 3: Cross multiply
    520.34x = 780.78 × 479.04
  4. Step 4: Simplify right side
    520.34x = 374,024.85
  5. Step 5: Solve for x
    x = 374,024.85/520.34
  6. Step 6: Final answer
    x = 718.81

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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.