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Finding the Fourth Proportional to 520.82, 718.80 and 287.99

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Solution

The fourth proportional to 520.82, 718.80 and 287.99 is: 397.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.82 : 718.80 = 287.99 : x
  2. Step 2: Convert to fraction form
    520.82/718.80 = 287.99/x
  3. Step 3: Cross multiply
    520.82x = 718.80 × 287.99
  4. Step 4: Simplify right side
    520.82x = 207,007.21
  5. Step 5: Solve for x
    x = 207,007.21/520.82
  6. Step 6: Final answer
    x = 397.46

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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.