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Finding the Fourth Proportional to 256.84, 383.84 and 208.80

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Solution

The fourth proportional to 256.84, 383.84 and 208.80 is: 312.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    256.84 : 383.84 = 208.80 : x
  2. Step 2: Convert to fraction form
    256.84/383.84 = 208.80/x
  3. Step 3: Cross multiply
    256.84x = 383.84 × 208.80
  4. Step 4: Simplify right side
    256.84x = 80,145.79
  5. Step 5: Solve for x
    x = 80,145.79/256.84
  6. Step 6: Final answer
    x = 312.05

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.