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Finding the Fourth Proportional to 645.30, 965.55 and 429.30

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Solution

The fourth proportional to 645.30, 965.55 and 429.30 is: 642.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 965.55 = 429.30 : x
  2. Step 2: Convert to fraction form
    645.30/965.55 = 429.30/x
  3. Step 3: Cross multiply
    645.30x = 965.55 × 429.30
  4. Step 4: Simplify right side
    645.30x = 414,510.62
  5. Step 5: Solve for x
    x = 414,510.62/645.30
  6. Step 6: Final answer
    x = 642.35

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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.