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Finding the Fourth Proportional to 521.56, 781.44 and 399.46

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Solution

The fourth proportional to 521.56, 781.44 and 399.46 is: 598.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.56 : 781.44 = 399.46 : x
  2. Step 2: Convert to fraction form
    521.56/781.44 = 399.46/x
  3. Step 3: Cross multiply
    521.56x = 781.44 × 399.46
  4. Step 4: Simplify right side
    521.56x = 312,154.02
  5. Step 5: Solve for x
    x = 312,154.02/521.56
  6. Step 6: Final answer
    x = 598.50

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 (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.