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Finding the Fourth Proportional to 465.20, 642.51 and 309.68

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Solution

The fourth proportional to 465.20, 642.51 and 309.68 is: 427.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    465.20 : 642.51 = 309.68 : x
  2. Step 2: Convert to fraction form
    465.20/642.51 = 309.68/x
  3. Step 3: Cross multiply
    465.20x = 642.51 × 309.68
  4. Step 4: Simplify right side
    465.20x = 198,969.28
  5. Step 5: Solve for x
    x = 198,969.28/465.20
  6. Step 6: Final answer
    x = 427.71

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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.