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Finding the Fourth Proportional to 521.42, 719.55 and 288.50

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Solution

The fourth proportional to 521.42, 719.55 and 288.50 is: 398.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.42 : 719.55 = 288.50 : x
  2. Step 2: Convert to fraction form
    521.42/719.55 = 288.50/x
  3. Step 3: Cross multiply
    521.42x = 719.55 × 288.50
  4. Step 4: Simplify right side
    521.42x = 207,590.18
  5. Step 5: Solve for x
    x = 207,590.18/521.42
  6. Step 6: Final answer
    x = 398.12

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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.