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Finding the Fourth Proportional to 284.78, 390.43 and 279.59

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Solution

The fourth proportional to 284.78, 390.43 and 279.59 is: 383.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.78 : 390.43 = 279.59 : x
  2. Step 2: Convert to fraction form
    284.78/390.43 = 279.59/x
  3. Step 3: Cross multiply
    284.78x = 390.43 × 279.59
  4. Step 4: Simplify right side
    284.78x = 109,157.37
  5. Step 5: Solve for x
    x = 109,157.37/284.78
  6. Step 6: Final answer
    x = 383.31

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.