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Finding the Fourth Proportional to 278.58, 384.47 and 208.51

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Solution

The fourth proportional to 278.58, 384.47 and 208.51 is: 287.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.58 : 384.47 = 208.51 : x
  2. Step 2: Convert to fraction form
    278.58/384.47 = 208.51/x
  3. Step 3: Cross multiply
    278.58x = 384.47 × 208.51
  4. Step 4: Simplify right side
    278.58x = 80,165.84
  5. Step 5: Solve for x
    x = 80,165.84/278.58
  6. Step 6: Final answer
    x = 287.77

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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.