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Finding the Fourth Proportional to 505.16, 697.13 and 308.78

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Solution

The fourth proportional to 505.16, 697.13 and 308.78 is: 426.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.16 : 697.13 = 308.78 : x
  2. Step 2: Convert to fraction form
    505.16/697.13 = 308.78/x
  3. Step 3: Cross multiply
    505.16x = 697.13 × 308.78
  4. Step 4: Simplify right side
    505.16x = 215,256.42
  5. Step 5: Solve for x
    x = 215,256.42/505.16
  6. Step 6: Final answer
    x = 426.12

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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.