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Finding the Fourth Proportional to 284.40, 421.20 and 277.20

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Solution

The fourth proportional to 284.40, 421.20 and 277.20 is: 410.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    284.40 : 421.20 = 277.20 : x
  2. Step 2: Convert to fraction form
    284.40/421.20 = 277.20/x
  3. Step 3: Cross multiply
    284.40x = 421.20 × 277.20
  4. Step 4: Simplify right side
    284.40x = 116,756.64
  5. Step 5: Solve for x
    x = 116,756.64/284.40
  6. Step 6: Final answer
    x = 410.54

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.