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Finding the Fourth Proportional to 521.77, 720.08 and 300.78

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Solution

The fourth proportional to 521.77, 720.08 and 300.78 is: 415.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.77 : 720.08 = 300.78 : x
  2. Step 2: Convert to fraction form
    521.77/720.08 = 300.78/x
  3. Step 3: Cross multiply
    521.77x = 720.08 × 300.78
  4. Step 4: Simplify right side
    521.77x = 216,585.66
  5. Step 5: Solve for x
    x = 216,585.66/521.77
  6. Step 6: Final answer
    x = 415.10

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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.