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Finding the Fourth Proportional to 645.80, 969.02 and 429.32

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Solution

The fourth proportional to 645.80, 969.02 and 429.32 is: 644.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.80 : 969.02 = 429.32 : x
  2. Step 2: Convert to fraction form
    645.80/969.02 = 429.32/x
  3. Step 3: Cross multiply
    645.80x = 969.02 × 429.32
  4. Step 4: Simplify right side
    645.80x = 416,019.67
  5. Step 5: Solve for x
    x = 416,019.67/645.80
  6. Step 6: Final answer
    x = 644.19

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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.