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Finding the Fourth Proportional to 521.38, 719.50 and 288.50

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Solution

The fourth proportional to 521.38, 719.50 and 288.50 is: 398.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.38 : 719.50 = 288.50 : x
  2. Step 2: Convert to fraction form
    521.38/719.50 = 288.50/x
  3. Step 3: Cross multiply
    521.38x = 719.50 × 288.50
  4. Step 4: Simplify right side
    521.38x = 207,575.75
  5. Step 5: Solve for x
    x = 207,575.75/521.38
  6. Step 6: Final answer
    x = 398.13

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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.