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Finding the Fourth Proportional to 253.05, 381.30 and 208.40

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Solution

The fourth proportional to 253.05, 381.30 and 208.40 is: 314.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.05 : 381.30 = 208.40 : x
  2. Step 2: Convert to fraction form
    253.05/381.30 = 208.40/x
  3. Step 3: Cross multiply
    253.05x = 381.30 × 208.40
  4. Step 4: Simplify right side
    253.05x = 79,462.92
  5. Step 5: Solve for x
    x = 79,462.92/253.05
  6. Step 6: Final answer
    x = 314.02

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.