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Finding the Fourth Proportional to 278.39, 383.86 and 208.34

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Solution

The fourth proportional to 278.39, 383.86 and 208.34 is: 287.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.39 : 383.86 = 208.34 : x
  2. Step 2: Convert to fraction form
    278.39/383.86 = 208.34/x
  3. Step 3: Cross multiply
    278.39x = 383.86 × 208.34
  4. Step 4: Simplify right side
    278.39x = 79,970.43
  5. Step 5: Solve for x
    x = 79,970.43/278.39
  6. Step 6: Final answer
    x = 287.26

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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.