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Finding the Fourth Proportional to 608.40, 839.88 and 412.20

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Solution

The fourth proportional to 608.40, 839.88 and 412.20 is: 569.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.40 : 839.88 = 412.20 : x
  2. Step 2: Convert to fraction form
    608.40/839.88 = 412.20/x
  3. Step 3: Cross multiply
    608.40x = 839.88 × 412.20
  4. Step 4: Simplify right side
    608.40x = 346,198.54
  5. Step 5: Solve for x
    x = 346,198.54/608.40
  6. Step 6: Final answer
    x = 569.03

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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.