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Finding the Fourth Proportional to 284.64, 387.78 and 278.70

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Solution

The fourth proportional to 284.64, 387.78 and 278.70 is: 379.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.64 : 387.78 = 278.70 : x
  2. Step 2: Convert to fraction form
    284.64/387.78 = 278.70/x
  3. Step 3: Cross multiply
    284.64x = 387.78 × 278.70
  4. Step 4: Simplify right side
    284.64x = 108,074.29
  5. Step 5: Solve for x
    x = 108,074.29/284.64
  6. Step 6: Final answer
    x = 379.69

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Why These Related Problems?

These problems maintain the same ratio (1.36) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.