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Finding the Fourth Proportional to 630.69, 870.66 and 520.80

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Solution

The fourth proportional to 630.69, 870.66 and 520.80 is: 718.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.69 : 870.66 = 520.80 : x
  2. Step 2: Convert to fraction form
    630.69/870.66 = 520.80/x
  3. Step 3: Cross multiply
    630.69x = 870.66 × 520.80
  4. Step 4: Simplify right side
    630.69x = 453,439.73
  5. Step 5: Solve for x
    x = 453,439.73/630.69
  6. Step 6: Final answer
    x = 718.96

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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.