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Finding the Fourth Proportional to 465.21, 642.51 and 309.69

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Solution

The fourth proportional to 465.21, 642.51 and 309.69 is: 427.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    465.21 : 642.51 = 309.69 : x
  2. Step 2: Convert to fraction form
    465.21/642.51 = 309.69/x
  3. Step 3: Cross multiply
    465.21x = 642.51 × 309.69
  4. Step 4: Simplify right side
    465.21x = 198,978.92
  5. Step 5: Solve for x
    x = 198,978.92/465.21
  6. Step 6: Final answer
    x = 427.72

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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.