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Finding the Fourth Proportional to 643.17, 887.16 and 407.19

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Solution

The fourth proportional to 643.17, 887.16 and 407.19 is: 561.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.17 : 887.16 = 407.19 : x
  2. Step 2: Convert to fraction form
    643.17/887.16 = 407.19/x
  3. Step 3: Cross multiply
    643.17x = 887.16 × 407.19
  4. Step 4: Simplify right side
    643.17x = 361,242.68
  5. Step 5: Solve for x
    x = 361,242.68/643.17
  6. Step 6: Final answer
    x = 561.66

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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.