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Finding the Fourth Proportional to 521.21, 719.28 and 285.16

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Solution

The fourth proportional to 521.21, 719.28 and 285.16 is: 393.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.21 : 719.28 = 285.16 : x
  2. Step 2: Convert to fraction form
    521.21/719.28 = 285.16/x
  3. Step 3: Cross multiply
    521.21x = 719.28 × 285.16
  4. Step 4: Simplify right side
    521.21x = 205,104.86
  5. Step 5: Solve for x
    x = 205,104.86/521.21
  6. Step 6: Final answer
    x = 393.52

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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.