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Finding the Fourth Proportional to 520.03, 780.18 and 259.71

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Solution

The fourth proportional to 520.03, 780.18 and 259.71 is: 389.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.03 : 780.18 = 259.71 : x
  2. Step 2: Convert to fraction form
    520.03/780.18 = 259.71/x
  3. Step 3: Cross multiply
    520.03x = 780.18 × 259.71
  4. Step 4: Simplify right side
    520.03x = 202,624.45
  5. Step 5: Solve for x
    x = 202,624.45/520.03
  6. Step 6: Final answer
    x = 389.64

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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.