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Finding the Fourth Proportional to 521.62, 719.81 and 288.74

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Solution

The fourth proportional to 521.62, 719.81 and 288.74 is: 398.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.62 : 719.81 = 288.74 : x
  2. Step 2: Convert to fraction form
    521.62/719.81 = 288.74/x
  3. Step 3: Cross multiply
    521.62x = 719.81 × 288.74
  4. Step 4: Simplify right side
    521.62x = 207,836.50
  5. Step 5: Solve for x
    x = 207,836.50/521.62
  6. Step 6: Final answer
    x = 398.45

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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.