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Finding the Fourth Proportional to 722.80, 997.40 and 428.06

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Solution

The fourth proportional to 722.80, 997.40 and 428.06 is: 590.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    722.80 : 997.40 = 428.06 : x
  2. Step 2: Convert to fraction form
    722.80/997.40 = 428.06/x
  3. Step 3: Cross multiply
    722.80x = 997.40 × 428.06
  4. Step 4: Simplify right side
    722.80x = 426,947.04
  5. Step 5: Solve for x
    x = 426,947.04/722.80
  6. Step 6: Final answer
    x = 590.68

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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.