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Finding the Fourth Proportional to 520.85, 718.77 and 287.97

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Solution

The fourth proportional to 520.85, 718.77 and 287.97 is: 397.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.85 : 718.77 = 287.97 : x
  2. Step 2: Convert to fraction form
    520.85/718.77 = 287.97/x
  3. Step 3: Cross multiply
    520.85x = 718.77 × 287.97
  4. Step 4: Simplify right side
    520.85x = 206,984.20
  5. Step 5: Solve for x
    x = 206,984.20/520.85
  6. Step 6: Final answer
    x = 397.40

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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.