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Finding the Fourth Proportional to 521.45, 719.60 and 288.57

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Solution

The fourth proportional to 521.45, 719.60 and 288.57 is: 398.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.45 : 719.60 = 288.57 : x
  2. Step 2: Convert to fraction form
    521.45/719.60 = 288.57/x
  3. Step 3: Cross multiply
    521.45x = 719.60 × 288.57
  4. Step 4: Simplify right side
    521.45x = 207,654.97
  5. Step 5: Solve for x
    x = 207,654.97/521.45
  6. Step 6: Final answer
    x = 398.23

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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.