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Finding the Fourth Proportional to 829.89, 1,145.21 and 619.65

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Solution

The fourth proportional to 829.89, 1,145.21 and 619.65 is: 855.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    829.89 : 1,145.21 = 619.65 : x
  2. Step 2: Convert to fraction form
    829.89/1,145.21 = 619.65/x
  3. Step 3: Cross multiply
    829.89x = 1,145.21 × 619.65
  4. Step 4: Simplify right side
    829.89x = 709,626.28
  5. Step 5: Solve for x
    x = 709,626.28/829.89
  6. Step 6: Final answer
    x = 855.08

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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.