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Finding the Fourth Proportional to 646.21, 891.78 and 351.49

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Solution

The fourth proportional to 646.21, 891.78 and 351.49 is: 485.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.21 : 891.78 = 351.49 : x
  2. Step 2: Convert to fraction form
    646.21/891.78 = 351.49/x
  3. Step 3: Cross multiply
    646.21x = 891.78 × 351.49
  4. Step 4: Simplify right side
    646.21x = 313,451.75
  5. Step 5: Solve for x
    x = 313,451.75/646.21
  6. Step 6: Final answer
    x = 485.06

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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.