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Finding the Fourth Proportional to 521.45, 782.28 and 278.25

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Solution

The fourth proportional to 521.45, 782.28 and 278.25 is: 417.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.45 : 782.28 = 278.25 : x
  2. Step 2: Convert to fraction form
    521.45/782.28 = 278.25/x
  3. Step 3: Cross multiply
    521.45x = 782.28 × 278.25
  4. Step 4: Simplify right side
    521.45x = 217,669.41
  5. Step 5: Solve for x
    x = 217,669.41/521.45
  6. Step 6: Final answer
    x = 417.43

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.