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Finding the Fourth Proportional to 520.90, 718.80 and 299.81

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Solution

The fourth proportional to 520.90, 718.80 and 299.81 is: 413.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.90 : 718.80 = 299.81 : x
  2. Step 2: Convert to fraction form
    520.90/718.80 = 299.81/x
  3. Step 3: Cross multiply
    520.90x = 718.80 × 299.81
  4. Step 4: Simplify right side
    520.90x = 215,498.33
  5. Step 5: Solve for x
    x = 215,498.33/520.90
  6. Step 6: Final answer
    x = 413.71

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.