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Finding the Fourth Proportional to 521.87, 720.19 and 300.81

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Solution

The fourth proportional to 521.87, 720.19 and 300.81 is: 415.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.87 : 720.19 = 300.81 : x
  2. Step 2: Convert to fraction form
    521.87/720.19 = 300.81/x
  3. Step 3: Cross multiply
    521.87x = 720.19 × 300.81
  4. Step 4: Simplify right side
    521.87x = 216,639.60
  5. Step 5: Solve for x
    x = 216,639.60/521.87
  6. Step 6: Final answer
    x = 415.12

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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.