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Finding the Fourth Proportional to 505.40, 697.40 and 309.02

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Solution

The fourth proportional to 505.40, 697.40 and 309.02 is: 426.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.40 : 697.40 = 309.02 : x
  2. Step 2: Convert to fraction form
    505.40/697.40 = 309.02/x
  3. Step 3: Cross multiply
    505.40x = 697.40 × 309.02
  4. Step 4: Simplify right side
    505.40x = 215,510.55
  5. Step 5: Solve for x
    x = 215,510.55/505.40
  6. Step 6: Final answer
    x = 426.42

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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.