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Finding the Fourth Proportional to 643.40, 887.90 and 348.67

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Solution

The fourth proportional to 643.40, 887.90 and 348.67 is: 481.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.40 : 887.90 = 348.67 : x
  2. Step 2: Convert to fraction form
    643.40/887.90 = 348.67/x
  3. Step 3: Cross multiply
    643.40x = 887.90 × 348.67
  4. Step 4: Simplify right side
    643.40x = 309,580.13
  5. Step 5: Solve for x
    x = 309,580.13/643.40
  6. Step 6: Final answer
    x = 481.16

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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.