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Finding the Fourth Proportional to 253.86, 380.79 and 208.53

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Solution

The fourth proportional to 253.86, 380.79 and 208.53 is: 312.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    253.86 : 380.79 = 208.53 : x
  2. Step 2: Convert to fraction form
    253.86/380.79 = 208.53/x
  3. Step 3: Cross multiply
    253.86x = 380.79 × 208.53
  4. Step 4: Simplify right side
    253.86x = 79,404.23
  5. Step 5: Solve for x
    x = 79,404.23/253.86
  6. Step 6: Final answer
    x = 312.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.