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Finding the Fourth Proportional to 505.79, 698 and 309.16

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Solution

The fourth proportional to 505.79, 698 and 309.16 is: 426.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.79 : 698 = 309.16 : x
  2. Step 2: Convert to fraction form
    505.79/698 = 309.16/x
  3. Step 3: Cross multiply
    505.79x = 698 × 309.16
  4. Step 4: Simplify right side
    505.79x = 215,793.68
  5. Step 5: Solve for x
    x = 215,793.68/505.79
  6. Step 6: Final answer
    x = 426.65

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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.