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Finding the Fourth Proportional to 510.91, 769.80 and 421.61

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Solution

The fourth proportional to 510.91, 769.80 and 421.61 is: 635.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    510.91 : 769.80 = 421.61 : x
  2. Step 2: Convert to fraction form
    510.91/769.80 = 421.61/x
  3. Step 3: Cross multiply
    510.91x = 769.80 × 421.61
  4. Step 4: Simplify right side
    510.91x = 324,553.11
  5. Step 5: Solve for x
    x = 324,553.11/510.91
  6. Step 6: Final answer
    x = 635.25

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1.5x scale

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.