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Finding the Fourth Proportional to 640.84, 881.71 and 622.69

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Solution

The fourth proportional to 640.84, 881.71 and 622.69 is: 856.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.84 : 881.71 = 622.69 : x
  2. Step 2: Convert to fraction form
    640.84/881.71 = 622.69/x
  3. Step 3: Cross multiply
    640.84x = 881.71 × 622.69
  4. Step 4: Simplify right side
    640.84x = 549,029.99
  5. Step 5: Solve for x
    x = 549,029.99/640.84
  6. Step 6: Final answer
    x = 856.74

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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.