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Finding the Fourth Proportional to 521.80, 720.29 and 356.11

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Solution

The fourth proportional to 521.80, 720.29 and 356.11 is: 491.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.80 : 720.29 = 356.11 : x
  2. Step 2: Convert to fraction form
    521.80/720.29 = 356.11/x
  3. Step 3: Cross multiply
    521.80x = 720.29 × 356.11
  4. Step 4: Simplify right side
    521.80x = 256,502.47
  5. Step 5: Solve for x
    x = 256,502.47/521.80
  6. Step 6: Final answer
    x = 491.57

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.