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Finding the Fourth Proportional to 521.89, 720.20 and 300.88

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Solution

The fourth proportional to 521.89, 720.20 and 300.88 is: 415.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.89 : 720.20 = 300.88 : x
  2. Step 2: Convert to fraction form
    521.89/720.20 = 300.88/x
  3. Step 3: Cross multiply
    521.89x = 720.20 × 300.88
  4. Step 4: Simplify right side
    521.89x = 216,693.78
  5. Step 5: Solve for x
    x = 216,693.78/521.89
  6. Step 6: Final answer
    x = 415.21

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1.5x scale

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.