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Finding the Fourth Proportional to 628.40, 940.82 and 422.56

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Solution

The fourth proportional to 628.40, 940.82 and 422.56 is: 632.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.40 : 940.82 = 422.56 : x
  2. Step 2: Convert to fraction form
    628.40/940.82 = 422.56/x
  3. Step 3: Cross multiply
    628.40x = 940.82 × 422.56
  4. Step 4: Simplify right side
    628.40x = 397,552.90
  5. Step 5: Solve for x
    x = 397,552.90/628.40
  6. Step 6: Final answer
    x = 632.64

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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.