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Finding the Fourth Proportional to 643.79, 888.29 and 407.31

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Solution

The fourth proportional to 643.79, 888.29 and 407.31 is: 562.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.79 : 888.29 = 407.31 : x
  2. Step 2: Convert to fraction form
    643.79/888.29 = 407.31/x
  3. Step 3: Cross multiply
    643.79x = 888.29 × 407.31
  4. Step 4: Simplify right side
    643.79x = 361,809.40
  5. Step 5: Solve for x
    x = 361,809.40/643.79
  6. Step 6: Final answer
    x = 562.00

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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.