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Finding the Fourth Proportional to 620.30, 855.51 and 445.74

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Solution

The fourth proportional to 620.30, 855.51 and 445.74 is: 614.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.30 : 855.51 = 445.74 : x
  2. Step 2: Convert to fraction form
    620.30/855.51 = 445.74/x
  3. Step 3: Cross multiply
    620.30x = 855.51 × 445.74
  4. Step 4: Simplify right side
    620.30x = 381,335.03
  5. Step 5: Solve for x
    x = 381,335.03/620.30
  6. Step 6: Final answer
    x = 614.76

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1.5x scale

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.