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Finding the Fourth Proportional to 639.84, 883.08 and 407.04

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Solution

The fourth proportional to 639.84, 883.08 and 407.04 is: 561.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.84 : 883.08 = 407.04 : x
  2. Step 2: Convert to fraction form
    639.84/883.08 = 407.04/x
  3. Step 3: Cross multiply
    639.84x = 883.08 × 407.04
  4. Step 4: Simplify right side
    639.84x = 359,448.88
  5. Step 5: Solve for x
    x = 359,448.88/639.84
  6. Step 6: Final answer
    x = 561.78

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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.