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Finding the Fourth Proportional to 521.87, 779.07 and 485.42

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Solution

The fourth proportional to 521.87, 779.07 and 485.42 is: 724.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.87 : 779.07 = 485.42 : x
  2. Step 2: Convert to fraction form
    521.87/779.07 = 485.42/x
  3. Step 3: Cross multiply
    521.87x = 779.07 × 485.42
  4. Step 4: Simplify right side
    521.87x = 378,173.73
  5. Step 5: Solve for x
    x = 378,173.73/521.87
  6. Step 6: Final answer
    x = 724.65

Related Problems

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Double scale
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Similar ratio
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.