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Finding the Fourth Proportional to 660.70, 991.05 and 622.90

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Solution

The fourth proportional to 660.70, 991.05 and 622.90 is: 934.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.70 : 991.05 = 622.90 : x
  2. Step 2: Convert to fraction form
    660.70/991.05 = 622.90/x
  3. Step 3: Cross multiply
    660.70x = 991.05 × 622.90
  4. Step 4: Simplify right side
    660.70x = 617,325.05
  5. Step 5: Solve for x
    x = 617,325.05/660.70
  6. Step 6: Final answer
    x = 934.35

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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.