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Finding the Fourth Proportional to 646.39, 886.20 and 634.69

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Solution

The fourth proportional to 646.39, 886.20 and 634.69 is: 870.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    646.39 : 886.20 = 634.69 : x
  2. Step 2: Convert to fraction form
    646.39/886.20 = 634.69/x
  3. Step 3: Cross multiply
    646.39x = 886.20 × 634.69
  4. Step 4: Simplify right side
    646.39x = 562,463.86
  5. Step 5: Solve for x
    x = 562,463.86/646.39
  6. Step 6: Final answer
    x = 870.16

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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.