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Finding the Fourth Proportional to 505.40, 697.55 and 308.84

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Solution

The fourth proportional to 505.40, 697.55 and 308.84 is: 426.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.40 : 697.55 = 308.84 : x
  2. Step 2: Convert to fraction form
    505.40/697.55 = 308.84/x
  3. Step 3: Cross multiply
    505.40x = 697.55 × 308.84
  4. Step 4: Simplify right side
    505.40x = 215,426.31
  5. Step 5: Solve for x
    x = 215,426.31/505.40
  6. Step 6: Final answer
    x = 426.25

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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.