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Finding the Fourth Proportional to 742.20, 1,113.57 and 280.28

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Solution

The fourth proportional to 742.20, 1,113.57 and 280.28 is: 420.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    742.20 : 1,113.57 = 280.28 : x
  2. Step 2: Convert to fraction form
    742.20/1,113.57 = 280.28/x
  3. Step 3: Cross multiply
    742.20x = 1,113.57 × 280.28
  4. Step 4: Simplify right side
    742.20x = 312,105.83
  5. Step 5: Solve for x
    x = 312,105.83/742.20
  6. Step 6: Final answer
    x = 420.51

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1.5x scale

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.