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Finding the Fourth Proportional to 445.70, 615.28 and 280

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Solution

The fourth proportional to 445.70, 615.28 and 280 is: 386.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    445.70 : 615.28 = 280 : x
  2. Step 2: Convert to fraction form
    445.70/615.28 = 280/x
  3. Step 3: Cross multiply
    445.70x = 615.28 × 280
  4. Step 4: Simplify right side
    445.70x = 172,278.40
  5. Step 5: Solve for x
    x = 172,278.40/445.70
  6. Step 6: Final answer
    x = 386.53

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.