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Finding the Fourth Proportional to 284.85, 427.28 and 79.40

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Solution

The fourth proportional to 284.85, 427.28 and 79.40 is: 119.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.85 : 427.28 = 79.40 : x
  2. Step 2: Convert to fraction form
    284.85/427.28 = 79.40/x
  3. Step 3: Cross multiply
    284.85x = 427.28 × 79.40
  4. Step 4: Simplify right side
    284.85x = 33,926.70
  5. Step 5: Solve for x
    x = 33,926.70/284.85
  6. Step 6: Final answer
    x = 119.10

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.