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Finding the Fourth Proportional to 521.87, 720.14 and 288.99

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Solution

The fourth proportional to 521.87, 720.14 and 288.99 is: 398.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.87 : 720.14 = 288.99 : x
  2. Step 2: Convert to fraction form
    521.87/720.14 = 288.99/x
  3. Step 3: Cross multiply
    521.87x = 720.14 × 288.99
  4. Step 4: Simplify right side
    521.87x = 208,111.81
  5. Step 5: Solve for x
    x = 208,111.81/521.87
  6. Step 6: Final answer
    x = 398.78

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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.