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Finding the Fourth Proportional to 643.54, 888.32 and 407.89

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Solution

The fourth proportional to 643.54, 888.32 and 407.89 is: 563.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.54 : 888.32 = 407.89 : x
  2. Step 2: Convert to fraction form
    643.54/888.32 = 407.89/x
  3. Step 3: Cross multiply
    643.54x = 888.32 × 407.89
  4. Step 4: Simplify right side
    643.54x = 362,336.84
  5. Step 5: Solve for x
    x = 362,336.84/643.54
  6. Step 6: Final answer
    x = 563.04

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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.