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Finding the Fourth Proportional to 640.68, 876.29 and 630.60

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Solution

The fourth proportional to 640.68, 876.29 and 630.60 is: 862.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.68 : 876.29 = 630.60 : x
  2. Step 2: Convert to fraction form
    640.68/876.29 = 630.60/x
  3. Step 3: Cross multiply
    640.68x = 876.29 × 630.60
  4. Step 4: Simplify right side
    640.68x = 552,588.47
  5. Step 5: Solve for x
    x = 552,588.47/640.68
  6. Step 6: Final answer
    x = 862.50

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.