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Finding the Fourth Proportional to 521.17, 719.19 and 288.30

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Solution

The fourth proportional to 521.17, 719.19 and 288.30 is: 397.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.17 : 719.19 = 288.30 : x
  2. Step 2: Convert to fraction form
    521.17/719.19 = 288.30/x
  3. Step 3: Cross multiply
    521.17x = 719.19 × 288.30
  4. Step 4: Simplify right side
    521.17x = 207,342.48
  5. Step 5: Solve for x
    x = 207,342.48/521.17
  6. Step 6: Final answer
    x = 397.84

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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.