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Finding the Fourth Proportional to 857.45, 1,286.55 and 511.47

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Solution

The fourth proportional to 857.45, 1,286.55 and 511.47 is: 767.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    857.45 : 1,286.55 = 511.47 : x
  2. Step 2: Convert to fraction form
    857.45/1,286.55 = 511.47/x
  3. Step 3: Cross multiply
    857.45x = 1,286.55 × 511.47
  4. Step 4: Simplify right side
    857.45x = 658,031.73
  5. Step 5: Solve for x
    x = 658,031.73/857.45
  6. Step 6: Final answer
    x = 767.43

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1.5x scale

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.