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Finding the Fourth Proportional to 521.53, 781.62 and 290.30

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Solution

The fourth proportional to 521.53, 781.62 and 290.30 is: 435.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.53 : 781.62 = 290.30 : x
  2. Step 2: Convert to fraction form
    521.53/781.62 = 290.30/x
  3. Step 3: Cross multiply
    521.53x = 781.62 × 290.30
  4. Step 4: Simplify right side
    521.53x = 226,904.79
  5. Step 5: Solve for x
    x = 226,904.79/521.53
  6. Step 6: Final answer
    x = 435.07

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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.