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Finding the Fourth Proportional to 643.63, 887.33 and 407.46

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Solution

The fourth proportional to 643.63, 887.33 and 407.46 is: 561.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.63 : 887.33 = 407.46 : x
  2. Step 2: Convert to fraction form
    643.63/887.33 = 407.46/x
  3. Step 3: Cross multiply
    643.63x = 887.33 × 407.46
  4. Step 4: Simplify right side
    643.63x = 361,551.48
  5. Step 5: Solve for x
    x = 361,551.48/643.63
  6. Step 6: Final answer
    x = 561.74

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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.