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Finding the Fourth Proportional to 538.15, 805.51 and 428.71

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Solution

The fourth proportional to 538.15, 805.51 and 428.71 is: 641.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    538.15 : 805.51 = 428.71 : x
  2. Step 2: Convert to fraction form
    538.15/805.51 = 428.71/x
  3. Step 3: Cross multiply
    538.15x = 805.51 × 428.71
  4. Step 4: Simplify right side
    538.15x = 345,330.19
  5. Step 5: Solve for x
    x = 345,330.19/538.15
  6. Step 6: Final answer
    x = 641.70

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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.