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Finding the Fourth Proportional to 521.00, 784.11 and 391.67

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Solution

The fourth proportional to 521.00, 784.11 and 391.67 is: 589.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.00 : 784.11 = 391.67 : x
  2. Step 2: Convert to fraction form
    521.00/784.11 = 391.67/x
  3. Step 3: Cross multiply
    521.00x = 784.11 × 391.67
  4. Step 4: Simplify right side
    521.00x = 307,115.30
  5. Step 5: Solve for x
    x = 307,115.30/521.00
  6. Step 6: Final answer
    x = 589.47

Related Problems

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Double scale
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Similar ratio
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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.