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Finding the Fourth Proportional to 630.70, 870.82 and 497.72

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Solution

The fourth proportional to 630.70, 870.82 and 497.72 is: 687.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.70 : 870.82 = 497.72 : x
  2. Step 2: Convert to fraction form
    630.70/870.82 = 497.72/x
  3. Step 3: Cross multiply
    630.70x = 870.82 × 497.72
  4. Step 4: Simplify right side
    630.70x = 433,424.53
  5. Step 5: Solve for x
    x = 433,424.53/630.70
  6. Step 6: Final answer
    x = 687.21

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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.