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Finding the Fourth Proportional to 678.47, 930.71 and 636.53

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Solution

The fourth proportional to 678.47, 930.71 and 636.53 is: 873.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.47 : 930.71 = 636.53 : x
  2. Step 2: Convert to fraction form
    678.47/930.71 = 636.53/x
  3. Step 3: Cross multiply
    678.47x = 930.71 × 636.53
  4. Step 4: Simplify right side
    678.47x = 592,421.77
  5. Step 5: Solve for x
    x = 592,421.77/678.47
  6. Step 6: Final answer
    x = 873.18

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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.